Upload
others
View
5
Download
0
Embed Size (px)
Citation preview
1 Copyright © 2020, North Penn School District
Student’s Name: ____________________
North Penn School District
Lansdale, PA 19446
MATHEMATICS SUMMER REVIEW
RESOURCE PACKET
TO BE COMPLETED IN PREPARATION FOR
ALGEBRA 2 5.0
This Resource Packet provides an overview, including examples, of key
problem solving skills that you learned in Algebra 1. In order to be
successful in Algebra 2 5.0, it is essential that you possess a high level of
mastery for these types of problems prior to beginning the school year. As
you will discover, the majority of our time in Algebra 2 will be spent on
learning entirely new and advanced concepts that you have never seen
before. This leaves little time for relearning old concepts.
This Resource Packet has been designed to support your demonstration of
mastery through completion of problems as presented in the Mathematics
Summer Review - Practice Problem Packet (provided separately). As noted
on the Practice Problem Packet, completion of this assignment is strongly
encouraged. Upon request on the first day of school, your teacher will
provide the solutions and will be available to answer any questions that may
arise. (See the Practice Problem Packet for specific details on grading and
follow-up testing on these review topics).
Make sure that you allocate an appropriate amount of time to complete this
packet before the beginning of the school year.
START EARLY – DO NOT PROCRASTINATE.
2 Copyright © 2020, North Penn School District
Mathematics Review
In preparation for ALGEBRA 2 5.0
RESOURCE PACKET
CONTENTS
SECTION TOPIC PAGE
1. Order of Operations 3
2. Solving Linear Equations 5
3. Solving Inequalities in One Variable 7
4. Slope and Equations of Lines 13
5. Solving Systems of Equations 26
6. Graphing Inequalities in Two Variables 30
7. Rules of Exponents 32
8. Operations with Polynomials 35
9. Factoring Polynomials 37
10. Radical Expressions 38
3 Copyright © 2020, North Penn School District
REVIEW SECTION 1 – ORDER OF OPERATIONS
Vocabulary
Numerical Expression: An expression, such as 6 + 5, that consists of
numerals combined by operations and names a particular number, called the
value of the expression.
Algebraic Expression: An expression, such as 2x + 3, that consists of
numerals and variables combined with operations.
In order to avoid misunderstandings and errors, mathematicians have agreed
on certain rules for computation called Order of Operations. (PEMDAS)
Order of Operations
P Represents grouping or inclusion symbols. The basic grouping symbols
are parentheses ( ), brackets [ ], and the fraction bar. Expressions
within grouping symbols should be treated as a single value and should
be evaluated first. The fraction bar indicates that the numerator and
the denominator should each be treated as a single value. When more
than one grouping symbol is used, evaluate within the innermost
grouping symbol first.
E Represents exponents. Perform all operations with exponents.
M Multiplication and Division are considered to be on the same level
D of operational importance. Therefore, perform all multiplication and
division in order from left to right.
A Addition and Subtraction are also on the same level of operational
S importance. Perform all addition and subtraction in order from left
to right.
4 Copyright © 2020, North Penn School District
Use the Order of Operations to simplify each expression.
Example 1: Evaluate 3 12 4− 3 12 4 3 3 0− = − =
Example 2: Evaluate 2 26 4 3 7− + 2 26 4 3 7 36 4 3 49− + = − +
36 12 49
24 49 73
= − +
= + =
Example 3: Evaluate ( )2
3 2 5 7+ ( ) ( )2 2
3 2 5 7 3 7 7+ =
( )3 49 7
147 7 21
=
= =
To evaluate an algebraic expression means to replace each variable by a
given value. Then apply the Order of Operations to simplify the result.
Example 4: Evaluate 2
3
2a
a b
−
+ if 5 and 3a b= =
2
3
5 2 25 2 23
5 27 325 3
− −= =
++
Example 5: Evaluate ( )22
8 33
a b b − +
if = =5 and 2a b
first
5 Copyright © 2020, North Penn School District
( )
( )
2
2
28 5 2 3 2
3
28 3 3 2
3
28 9 3 2
3
272 6
3
278 52
3
− +
+
+
+
=
REVIEW SECTION 2 – SOLVING LINEAR EQUATIONS
1) Multiply using the Distributive Property if necessary
2) Undo addition or subtraction
3) Undo multiplication or division
Example 1:
+ =−
=−
=−
5 8 2
5 10
2
y
y
y
Example 2:
34 16
23
122
8
x
x
x
+ =
=
=
Example 3:
Subtract 8
Divide by 5
Subtract 4
Multiply by 2
3
6 Copyright © 2020, North Penn School District
− =
=
=
1 54
64
24
x
x
x
Example 4:
( )10 2 5
10 20 5
10 25
25 5
10 2
z
z
z
z
− =
− =
=
= =
Example 5:
( )− = −
− = −
− =−
2 7 2 14
2 14 2 14
14 14
f f
f f
Example 6:
− =− +
=
20 3 3 5
20 5
x x
Example 7:
Use the distributive property
Add 20
Divide by 10 (Don’t forget to
simplify)
Distribute
Subtract 2f
Since -14 = -14 is always true, the original
equation is an identity and the solution set
includes all Real numbers.
Add 3x
Since 20 5, there are no solutions that
make it true. Therefore, there is no
solution for this equation.
Add 1
Multiply by 4
7 Copyright © 2020, North Penn School District
( ) ( )− + =− − +
− + = −
= −
− =−
=
2 5 10 3 2
2 10 10 3 2
2 3 2
2
2
x x
x x
x x
x
x
Example 8:
( )2 4 2 7 3
2 4 2 7 3
4 4 7 3
4 3 3
7 3
3
73
7
x x
x x
x x
x x
x
x
x
− − = +
− + = +
− = +
− = +
− =
=−
=−
Distribute
Combine like terms
Subtract 3x
Divide by -1
Distribute
Combine like terms
Subtract 4
Subtract 3x
Divide by -7
Rewrite in simplest terms.
8 Copyright © 2020, North Penn School District
REVIEW SECTION 3 – SOLVING INEQUALITIES
IN ONE VARIABLE
Properties of Inequalities
Equivalent Inequalities are inequalities that have the same solution.
Addition Property of Inequalities: Adding a constant or variable term
to both sides of an inequality does not change the inequality.
Numerical Example:
4 17
4 3 17 3
7 20
+ +
4 3 17 3+ + Add 3 to
Algebraic Example 1 (add constant to both sides):
3 7 5 4
3 7 7 5 4 7
3 5 11
x x
x x
x x
− +
− + + +
+
4 3 17 3+ + Add 3
Algebraic Example 2 (add variable term to both sides):
11 4 2 3
11 4 2 2 3 2
13 4 3
x x
x x x x
x
− − +
− + − + +
−
Subtraction Property of Inequalities: Subtracting a constant or
variable term from both sides of an inequality does not change the
inequality. (Same idea as addition property of inequality)
Numerical Example:
31 8
31 6 8 6
25 2
− −
4 3 17 3+ + Add 3 to
Algebraic Example 1 (subtract constant from both sides):
8 5 3 8
8 5 8 3 8 8
8 13 3
x x
x x
x x
− +
− − + −
−
Given (true statement)
Add 3 to both sides
New inequality (still true!)
Given
Add 7 to both sides
Inequality stays the same!
Given (true statement)
Subtract 6 from both sides
New inequality (still true!)
Given
Subtract 8 from both sides
Inequality stays the same!
Given
Add 2x to both sides
Inequality stays the same!
9 Copyright © 2020, North Penn School District
Multiplication Property of Inequalities: Multiplying both sides of an
inequality by a positive constant does not change the inequality.
However, multiplying by a negative constant switches the direction of
the inequality.
Numerical Example 1 (multiply by a positive constant):
8 13
8 2 13 2
16 26
−
− • •
−
4 3 17 3+ + Add 3 to
Numerical Example 2 (multiply by a negative constant):
15 4
15 3 4 3
45 12
•− •−
− −
4 3 17 3+ + Add 3 to
Algebraic Example 1 (multiply by a positive constant):
( ) ( )
117
21
2 17 22
34
x
x
x
4 3 17 3+ + Add 3
Algebraic Example 2 (multiply by a negative constant):
36
14
14 3 146
3 14 3
28
x
x
x
−
− − − −
.Add 3
Since division by some number is the same as multiplying by the
reciprocal of that number, it should seem reasonable that the rules
for division in inequalities are the same as those outlined above for
multiplication in an inequality. See the next page for details.
Given (true statement)
Multiply both sides by 2
New inequality (still true!)
Given
Multiply both sides by 2
Inequality stays the same!
Given (true statement)
Multiply both sides by -3
Direction of inequality switches.
Given
Multiply both sides by 3
14−
Direction of inequality switches.
10 Copyright © 2020, North Penn School District
Division Property of Inequalities: Dividing both sides of an inequality
by a positive constant does not change the inequality however dividing
by a negative constant switches the direction of the inequality.
Numerical Example 1 (division by a positive constant):
2 30
2 30
2 21 15
4 3 17 3+ + Add 3 to
Numerical Example 2 (division by a negative constant):
44 22
44 22
11 114 2
−
−
− −
−
4 3 17 3+ + Add 3 to
Algebraic Example 1 (division by a positive constant):
5 35
5 35
5 57
x
x
x
4 3 17 3+ + Add 3
Algebraic Example 2 (division by a negative constant):
7 21
7 21
7 73
x
x
x
−
−
− −
−
4 3 17 3+ + Add 3
NOTE: The key to successful transformations of
inequalities using multiplication or division is as follows:
When you multiply or divide by a negative number (i.e.
when the number “doing the work” is negative), the
direction of the inequality sign changes.
Given (true statement)
Divide both sides by 2
New inequality (still true!)
Given
Divide both sides by 5
Inequality stays the same!
Given (true statement)
Divide both sides by -11
Direction of inequality switches.
Given
Divide both sides by -7
Direction of inequality switches.
11 Copyright © 2020, North Penn School District
Rewriting Inequalities:
Generally, inequalities are written with the variable on the left side of
the inequality sign. When you solve an inequality, sometimes the
variable ends up on the right side so you need to rewrite the inequality
into an easier form to graph properly.
Examples:
Rewrite 5 x as 5x
Rewrite 7 x− as 7x −
Rewrite 2
5x− as
2
5x −
Remember: As seen in all of these examples, the arrow point of
the inequality sign always points to the same number or variable as
in its original form. However, the arrow on your graph now points
in the same direction as the inequality.
Graphing Inequalities
When you solve an inequality, one of the key ways to represent your
solution is by graphing the solution on a number line. The graph of an
inequality in one variable is the set of points on a number line that
represent all solutions to the inequality.
Example 1: Graph 3 › x
Solution: Rewrite as x ‹ 3.
Graph with an open circle at x = 3.
Shade region of number line with values that
are less than 3 as indicated by the
inequality.
Remember: Always use an open circle for the ‹ or › inequality
symbols to show that the solution does not include a particular
value. (Notice that with the variable on the left, the inequality
sign points in the same direction as the arrow on the graph.)
4 3 2 1 0 -1 -2
12 Copyright © 2020, North Penn School District
Example 2: Graph x ≥ 4
Solution: Graph with a closed circle at x = 4.
Shade region of number line with values that
are greater than or equal to 4 as indicated
by the inequality.
Remember: Always use a closed circle for the ≤ or ≥ inequality
symbols to show that the solution does include a particular value.
Solving Inequalities and Graphing Solution
Example 3: Solve and Graph
- 7 6
1
x
x
−
Add 7 to each side
Graph
Example 4: Solve and Graph
x+2 7
x 5
Subtract 2 from each side
Graph
More Examples – Solving Inequalities with Various Strategies
Example 5: Solve and Graph
8 7 6 5 4 3 2
4 3 2 1 0 -1 -2
8 7 6 5 4 3 2
Multiply both sides by 3
to “clear” fractions.
30 25 20 15 10 5 0
53
3 * 5 *33
15
x
x
x
13 Copyright © 2020, North Penn School District
Example 6: Solve and Graph
Example 7: Solve and Graph 3x + 2 › 14
3x › 12 Subtract 2
x › 4 Divide by 3
Example 8: Solve and Graph 4(x - 1) ≥ 8
4x – 4 ≥ 8 Distribute
4x ≥ 12 Add 4
x ≥ 3 Divide by 4
Example 9: Solve and Graph 11 – 2x ≥ 3x + 16
-2x ≥ 3x + 5 Subtract 11
-5x ≥ 5 Subtract 3x
x ≤ -1 Divide by -5
Divide by –4.
Since dividing by a
negative number,
direction of inequality
sign must be changed.
3 2 1 0 -1 -2 -3
8 7 6 5 4 3 2
7 6 5 4 3 2 1
2 1 0 -1 -2 -3 -4
− −
-4x 8
-4x 8
4 4
x -2
14 Copyright © 2020, North Penn School District
REVIEW SECTION 4 – SLOPE AND EQUATIONS OF LINES
When graphing a linear equation, the line has a certain amount of “steepness”
associated with it. In order to measure the amount of steepness, we define
the “slope” of the line as the following ratio:
=Change in y direction Rise
Slope =m =Change in x direction Run
.
The terms “Rise” and “Run” are used in Algebra to describe the steepness of
a line. The vertical portion of a graph from one distinct point to another
(Rise) as compared to the dimension of the horizontal distance from one
point to another (Run). When taken together, Rise over Run tells the story
of the slope, or steepness, of the steps. The slope of a linear equation is the
same at any point along the graph of the equation.
DETERMINING SLOPE DIRECTLY FROM A GRAPH
1) Identify the coordinates of a point on the graph where the line
crosses at the intersection of grid lines on the graph paper.
2) Identify a second point which also crosses at the intersection of
grid lines.
3) Starting at the first point, draw a step using only vertical and
horizontal moves that will take you to the second point. The
amount of movement in the vertical direction is the “change in y”
and the amount of movement in the horizontal direction is the
“change in x.” Use these values to calculate the slope as shown
above.
NOTE:
Movement is a move in the positive y direction
Movement is a move in the negative y direction
Movement is a move in the positive x direction
Movement is a move in the negative x direction
15 Copyright © 2020, North Penn School District
NOTE: As shown in the above graph, any line that has a positive
value for slope will rise from left to right.
NOTE: As shown in the above graph, any line that has a negative
value for slope will fall from left to right.
Example 1: Find the slope of the line
shown in the graph to the right.
Pick two convenient points that cross
at the intersection of grid lines on the
graph paper. Since slope is the same
at all points along the graph, the size
of the “step” created does not matter.
Based on a movement of +3 in the y
direction and +2 in the x direction, the
slope of this equation would be 3
2.
Example 2: Find the slope of the line
shown in the graph to the right.
Based on a movement of +8 in the y
direction and -4 in the x direction, the
slope of this equation would be −
8
4
which is then simplified to -2.
3 = +y
2x = +
8 = +y
4 = −x
SCALE: Each block is 1 unit wide by 1 unit high
SCALE: Each block is 1 unit wide by 1 unit high
16 Copyright © 2020, North Penn School District
DETERMINING SLOPE FROM TWO POINTS
Since the slope of a line (usually labeled “m”) represents the ratio of
change in y direction to change in x direction, then slope may be
calculated from two ordered pair solutions ( ) ( )2211 ,and, yxyx for the
equation by the following formula:
( )( )
− = =
−
2 1
2 1
yDifference in y coordinatesSlope = m =
Difference in x coordinates x
y y
x x
Example 1:
Find the slope of a line that goes through the points (-2,-4)
and (3, 8).
The ordered pair (-2, -4) can be labeled Point 1 and (3, 8) is
labeled Point2. The x and y coordinates for each point are
labeled using subscripts to keep track of the numbers that will
be used in the slope calculation.
1 1
Point 1
( 2, 4 )
,x y
− −
2 2
Point 2
( 3, 8 )
,x y
( )( )( )( )
8 4Difference in y coordinates 12Slope = m =
Difference in x coordinates 3 2 5
− −= =
− −
Example 2:
Find the slope of a line that goes through the points (4, -2)
and (-1, 5).
1 1
Point 1
( 4, 2 )
,x y
− −
2 2
Point 2
( 1, 5 )
,x y
( )( )( )( )
5 2 7Difference in y coordinates 7Slope = m =
Difference in x coordinates 1 4 5 5
− −= = = −
− − −
17 Copyright © 2020, North Penn School District
DETERMINING SLOPE FROM THE SLOPE-INTERCEPT
FORM OF AN EQUATION
If an equation is written in the slope intercept form of y= mx + b,
then the slope may be obtained directly from m, the numerical
coefficient of x.
Example:
Given the equation y x= +3 1 , the slope of this equation
will be 3
1
3
1or
−
−.
SPECIAL VALUES OF SLOPE
➢ SLOPE = 0
The slope of a horizontal line is always zero (0).
Example 2:
Find the slope of a line that goes through the points (-6, 4)
and (18, 4).
Example 1: Find the slope of the line
shown in the graph to the right.
The movement from one point to the
other is +7 in the x direction but zero
in the y direction (since y values at
both points are the same). As a result
0
07
= = =
ym
x
0 =y because y
values are the same
at both points
7 = +x
SCALE: Each block is 1 unit wide by 1 unit high
18 Copyright © 2020, North Penn School District
1 1
Point 1
( 6, 4 )
,x y
−
2 2
Point 2
( 18, 4 )
,x y
( )
( )( )4 4 0Difference in y coordinates
Slope = m = 0Difference in x coordinates 18 6 24
−= = =
− −
➢ UNDEFINED SLOPE or NO SLOPE
The slope of a vertical line is considered to be “Undefined” and is
sometimes called “No Slope.”
Example 4:
Find the slope of a line that goes through the points (-9, -16)
and (-9, 3).
1 1
Point 1
( 9, 16 )
,x y
− −
2 2
Point 2
( 9, 3 )
,x y
−
( )( )( )( )
Difference in y coordinatesSlope = m =
Difference in x coordinates
3 16 19
9 9 0Undefined
− −= = =
− − −
Example 3: Find the slope of the line
shown in the graph to the right.
The movement from one point to the
other is +6 in the y direction but zero
in the x direction (since x values at
both points are the same). As a result
6
0
= = =
ym Undefined
x
0 =x because x
values are the same
at both points 6 = +y
SCALE: Each block is 1 unit wide by 1 unit high
19 Copyright © 2020, North Penn School District
20 Copyright © 2020, North Penn School District
WRITING LINEAR EQUATIONS
While the slope intercept form of a linear equation, = +y mx b , is one of the
most convenient forms to use in order to easily graph a linear equation, the
point-slope form of a linear equation is the preferred format to use when
writing linear equations for a line based on a given value of slope along with
the coordinates of a solution point on the line.
The point-slope form of a linear equation is:
( ) ( )− = −1 1y y m x x
( )1 1
: = slope
, = coordinates of an ordered pair
on the line (and therefore, part
of solution set)
where m
x y
Upon careful examination, you will see that the point-slope form of a linear
equation is nothing more than an algebraic transformation of the slope
formula for a general value of x and y:
( )( )
( ) ( )−
= − = −−
11 1
1
ym ; Cross multiply to obtain:
x
yy y m x x
x
WRITING LINEAR EQUATIONS GIVEN A POINT AND A
SLOPE
Example: Write the equation of a line that has a slope of −3
4 and goes
through the point ( )−, )3 1 .
21 Copyright © 2020, North Penn School District
( ) ( )
( )( ) ( )
: ; ;= − = = −
− = −
− − = − −
+ = − +
= − + −
= − +
1 1
1 1
33 1
4
31 3
43 9
14 4
3 91
4 43 5
4 4
Given m x y
y y m x x
y x
y x
y x
y x
WRITING LINEAR EQUATIONS GIVEN TWO POINTS
Example: Write the equation of a line that goes through the points
( )− ,2 5 and ( )− −,6 9 .
The starting point for this problem is then to first find the slope of the line
and then find the equation in the same manner as demonstrated in the last
example:
=− = −
= =−
1 2
1 2
Given: x 2 x 6
5 9y y
( )( )
( )( )( ) ( )( )
− −− −= = = =
− − − − −
2 1
2 1
9 5y 14 7Slope = m =
x 6 2 4 2
yy
x x
( ) ( )
( ) ( )( )
− = −
− = − −
− = +
= + +
= +
1 1
75 2
27
5 72
77 5
27
122
y y m x x
y x
y x
y x
y x
Note that no numbers are
substituted into the
equation for the x and y
variables that do not have a
subscript.
22 Copyright © 2020, North Penn School District
GRAPHING LINEAR EQUATIONS
The graph of a linear equation is a straight line. When you first started to
graph linear equations, you probably picked several values of x, calculated
the corresponding values of y using the given equation, plotted the points
and then connected the points with a line. You have also learned to graph
linear equations by three other methods: a) using a given point on the line
and slope, b) using slope and y-intercept and c) using x and y-intercepts. In
Algebra 2, you will be expected to be able to use these three “shortcut”
methods to graph linear equations. You will also be expected to develop a
linear equation from only a graph of the equation.
GRAPHING LINEAR EQUATIONS USING A POINT AND SLOPE
1) If given a point on a line and the slope of the line through that point, the
location of the given point represents a starting point for drawing the
graph. Plot the given point.
2) The slope, commonly represented by the variable m, indicates the
direction to “move away” from this given point in a stepwise manner.
Using the location of the given point as a starting point, find a second
point on the graph by moving away from the given point using the vertical
and horizontal components given by the slope. Find one point on either
side of the given point to confirm the trend indicated by slope.
3) Draw a straight line through given point and the points constructed
through use of the slope.
A few notes on interpreting “direction of movement” from slope (m)
➢ If m = an integer value like 2, rewrite it as 2
1 to represent a move of
2 in the positive y direction ( ) and 1 in the positive x direction (→).
Remember that this value of slope could also be represented by −
−
2
1
which would be 2 in the negative y direction () and 1 in the negative x
direction ().
➢ If m is a negative value like −2
3, remember that you can associate the
negative sign with either the numerator −
2
3 or the denominator
−
2
3 to obtain the correct direction of movement from a given point.
23 Copyright © 2020, North Penn School District
EXAMPLE: Graph the equation of a line that goes through the
point (2, -1) and has a slope of −3
4.
Step 1: Graph the given point in Quadrant IV as shown on the
graph below.
Step 2: Plot additional points based on the stepwise movement
given by the slope. Since m = −3
4, then move away from
the given point by moving 3 units in the negative y
direction and then 4 units in the positive x direction
(i.e. =− =,y x3 4 ). Another option is to move 3 units in
the positive y direction followed by 4 units in the
negative x direction (i.e. = =−,y x3 4 ).
Step 3: Draw a straight line through the given point and the
constructed points.
3y = +
4x = +
4x = −
3y = −
x Starting point
at (2, -1)
y
SCALE: Each block is 1 unit wide by 1 unit high
24 Copyright © 2020, North Penn School District
A reminder about “Special Cases” where Slope = 0 or is “Undefined”
➢ SLOPE = 0: The graph of an equation such as y= (some value) is
always represented by a horizontal line and is commonly referred to as
a Constant Function. Since all points along a horizontal line have the
same value for the y-coordinate, the value of y is always equal to
zero and as a result, the slope of this line is always zero (0).
EXAMPLE: Graph the equation of a line that goes through the point (4, -3)
and has a slope of 0. What is the equation of this line?
➢ SLOPE = UNDEFINED: The graph of an equation such as
x= (some value) is always represented by a vertical line. Since all
points along a vertical line have the same x-coordinate, the value of
x is always equal to zero and as a result, the slope of this line is
always “Undefined.” An undefined slope is sometimes also described
as “No Slope.”
EXAMPLE: Graph the equation of a line that goes through the point (3, 2)
and has an undefined slope. What is the equation of this line?
x
y
=3x
x
y
= −3y
SCALE: Each block is 1 unit wide by 1 unit high
SCALE: Each block is 1 unit wide by 1 unit high
25 Copyright © 2020, North Penn School District
GRAPHING LINEAR EQUATIONS BY SLOPE AND Y-INTERCEPT
SLOPE-INTERCEPT FORM:
= +
= slopewhere
= y-intercept
my mx b
b
1) If the equation is not in the “slope-intercept” form of y = mx+b,
complete the necessary transformations to get it into this form.
2) The y-intercept is given by the value of b in the equation and is the
starting point for completing this graph. This point would be graphed
on the y-axis as the ordered pair (0, y-intercept).
3) The slope is given by the value of m and indicates the direction to
“move away” from the y-intercept in a stepwise manner. Using the
y-intercept as a starting point, find a second point on the graph by
moving away from the y-intercept. Find one point on either side of
the y-intercept to confirm the trend indicated by slope.
4) Draw a straight line through y-intercept and constructed points.
Example 1: Graph: 5
13
y x= −
Identify the key graphing parameters and graph:
y-intercept:
Since b = -1. the y-intercept
is located at (0, -1).
Slope:
Since m = 5
3, then “move away”
from the y-intercept starting point
by moving 5 units in the positive y
direction and then 3 units in the
positive x direction. It could also
mean a move of 5 units in the
negative y direction and then 3 units in the negative x direction
since −
−
5
3 = 5
3.
5 = +y
3x = +
3x = −
5 = −y
x
Starting point is at
y intercept (0, -1)
SCALE: Each block is 1 unit wide by 1 unit high
26 Copyright © 2020, North Penn School District
Example 2: Graph: 2
35
y x= − +
Identify the key graphing parameters and graph:
y-intercept:
Since b = 3. the y-intercept
is located at (0, 3).
Slope:
The slope m = 2
5− which can be
rewritten as 2
5
− or 2
5−. Using the
value of 2
5
− , “move away” from the
y-intercept by moving 2 units in
the negative y direction and then 5
units in the positive x direction. Another option is to use the
value of 2
5− which would mean to “move away” from the y-
intercept by moving 2 units in the positive y direction and then
5 units in the negative x direction.
Example 3: Graph: − + =2 3 6x y
Step 1: First convert equation to slope intercept form:
( )
Addition Property of Equality
Multiplication Property of Equality
− + =
+ +
= +
= +
2 3 3
2 2
1 13 2 3
3 3
21
3
x y
x x
y x
y x
.
y
2 = +y
5 = −x
5 =x
2 = −y
x
Starting point is at
y intercept (0, 3)
SCALE: Each block is 1 unit wide by 1 unit high
27 Copyright © 2020, North Penn School District
Step 2: Identify the key graphing parameters and graph:
y-intercept: Since b = 1. the y-intercept is located at
(0, 1).
Slope: Since m = 2
3, then “move away” from the y-
intercept starting point by moving 2 units in
the positive y direction and then 3 units in
the positive x direction. It could also mean
a move of 2 units in the negative y direction
and then 3 units in the negative x direction
since −
−
2
3 = 2
3.
y
x
Starting point is at
y intercept (0, 1)
SCALE: Each block is 1 unit wide by 1 unit high
28 Copyright © 2020, North Penn School District
REVIEW SECTION 5 – SOLVING SYSTEMS OF EQUATIONS
Vocabulary: Two or more linear equations with the same variables represent
a system of linear equations or a linear system.
Three possible cases exist when solving a system of equations:
1) If one ordered pair satisfies all of the equations in the
system, then the solution is that ordered pair, (x, y).
2) If an infinite number of ordered pairs satisfy all of the
equations in the system, then the graphs of both equations
are the same line.
3) If no ordered pairs satisfy all of the equations, then the
graphs of these equations are parallel, and therefore do not
intersect. As a result, the system has no solution, and is
denoted by the Greek symbol .
When the solution to a system of linear equations in two variables is
an ordered pair of numbers (x, y), you can check your answer by
substituting this ordered pair back into each original equation of the
system. The result should be a true statement. The point (x, y)
lies on the graph of each equation, and is the point of intersection of
the two lines.
Method #1: SOLVING SYSTEMS OF EQUATIONS GRAPHICALLY
Example: Solve the system by “Graphing”. -3x + y = -7
2x + 2y = 10
Solution: Rewrite each equation in slope-intercept form.
1) -3x + y = -7 y = 3x –7 Slope: 3 y int: (0. –7)
2) 2x + 2y = 10 y = -x + 5 Slope: -1 y int: (0, 5)
29 Copyright © 2020, North Penn School District
Method #2: SOLVING SYSTEMS
OF EQUATIONS BY LINEAR
COMBINATION (also known as Elimination)
The objective in this method is to get the coefficients of one variable
to be opposite numbers.
Example: Solve the system by “Elimination.” 4x - 3y = 11
3x + 2y = -13
To eliminate the y
4x - 3y = 11 Multiply by 2 8x - 6y = 22
3x + 2y = -13 Multiply by 3 9x + 6y = -39
Add the equations 17x = -17
Solve for x x = -1
Now substitute -1 for x in either of the original equations, and solve for y.
3x + 2y = -13
3(-1) + 2y = -13 Substitute –1 for x
– 3 + 2y = -13 Simplify
2y = -10 Add 3 to each side
y = -5 Solve for y
The solution is the ordered pair ( -1, -5 ).
•
•
• Solution to system is given by
coordinates of intersection of
the two equations. In this case,
the solution is (3, 2)
Graph of Equation # 1 Graph of Equation # 2
30 Copyright © 2020, North Penn School District
Method #3: SOLVING SYSTEMS OF EQUATIONS BY SUBSTITUTION
This method of solving systems by substitution should be considered
when at least one of the variables in the system of equations has a
coefficient of one (1) as demonstrated in the following examples:
Example 1: Solve the system by “Substitution.” -3x + y = -11
5x + 3y = 9
Since the variable y in the first equation has a coefficient of 1, solve
that equation for y in terms of x.
y = 3x - 11
Next substitute 3x - 11 for y in the other equation and solve for x.
5x + 3y = 9
5x + 3(3x – 11) = 9 Substitute 3x - 11 for y
5x + 9x –33 = 9 Distribute the 3
14x – 33 = 9 Combine like terms
14x = 42 Add 33 to each side
x = 3 Divide each side by 14
Find the value of y by substituting 3 for x in one of the original
equations (your choice).
-3(3) + y = -11 or 5(3) + 3y = 9
-9 + y = -11 15 + 3y = 9
y = -2 3y = -6
31 Copyright © 2020, North Penn School District
y = -2
The solution is the ordered pair ( 3, -2 ).
32 Copyright © 2020, North Penn School District
Example 2: Solve the system by “Substitution”. -3x + 4y = 16
x - 3y = -7
Since the variable x in the second equation has a coefficient of 1,
solve that equation for x in terms of y:
x = 3y - 7
Substitute 3y - 7 for x in the first equation and solve for y.
-3x + 4y = 16
-3(3y – 7) + 4y = 16 Substitute 3y - 7 for x
-9y + 21 + 4y = 16 Distribute the -3
-5y +21 = 16 Combine like terms
-5y = -5 Subtract 21 from both sides
y = 1 Divide each side by -5
Find the value of x by substituting 1 for y in one of the original
equations (your choice).
-3x + 4(1) = 16 or x – 3(1) = -7
-3x = 12 x = -4
x= -4
The solution is the ordered pair ( -4, 1 ).
33 Copyright © 2020, North Penn School District
REVIEW SECTION 6 – INEQUALITIES IN TWO VARIABLES
GRAPHING A LINEAR INEQUALITY IN TWO VARIABLES
Example 1: Graph x – y < 2
a) The corresponding equation is x – y = 2. In
slope-intercept form, this equation is y = x – 2.
Graph the boundary line using the y-intercept of -2
and the slope of 1. This line should be a dashed
line, or a broken line, to show that the points on
the line are not solutions since the original
inequality is only “ ”, not “ ”.
b) Pick a point that is not on the line, and use its
coordinates to determine the region to shade. For
ease of calculation, always consider using the origin (0,0) as the test
point unless it is on the line. Substituting the values of the
coordinates into the original inequality will result in either a
true or false statement.
c) Using (0, 0) as a test point in the given inequality x – y < 2,
results in 0 - 0 < 2, which is a true statement. Since the test
point generated a true statement, shade the same region as the test
point. In this case, shade above the line. This shaded region
represents the solution set of the given inequality, and consists of all
points above the graph of y = x – 2.
OR
If the coordinates had generated a false statement, then the region
on the other side of the line would have been shaded instead. The
actual solution set would have been the region that did not contain the
test point.
NOTE: The type of line used for the boundary between solution
points and non-solution points always depends on the type of inequality
given in the original problem.
Inequality Symbol “Boundary” line type
or Dashed or broken line
y
Test Point (0, 0)
Any point in shaded
region is a member of the solution set.
Points on line are excluded from solution
set in this example
(dashed line).
34 Copyright © 2020, North Penn School District
or Solid line
Example 2: Graph 2x + 3y -6
a) The corresponding equation is 2x + 3y -6= . In
slope-intercept form, this equation is 2
y = - x - 23
.
Graph this line using a y-intercept of -2 and a slope
of 2
-3
. Draw a solid line to show that the points on
the line are part of the solution set since the
original inequality is “ ”, and not just “ ”.
b) Pick a point that is not on the line, and use its
coordinates to determine the region to shade.
Again, for ease of calculation, always consider using the origin (0,0)
as the test point unless it is on the line. If (0,0) is on the boundary
line, you must try a different test point. Substituting the values of
the coordinates into the original inequality results in either a true or
false statement.
c) Using (0, 0) as a test point in the given inequality 2x + 3y -6 ,
results in ( ) ( )2 0 + 3 0 -6 , which is false! Since the test point
generated a false statement, shade the region on the other side of
the line. In this case, shade below the line. This shaded region
represents the solution set of the given inequality, and consists of all
points below the graph of 2
y = - x - 23
.
Testing another point on the other side of the boundary line confirms
that the lower area of this graph contains all of the solution points
for this inequality. 2x + 3y -6
At test point (-4, -3): ( ) ( )2 -4 + 3 -3 -6
-17 -6
which is true. Therefore, shade the area in the same region as this
test point.
y
First Test
Point (0, 0)
Any point in shaded
region is a member of the solution set.
Points on line are
included in solution set in this example
(solid line).
Second
Test Point
(0, 0)
35 Copyright © 2020, North Penn School District
36 Copyright © 2020, North Penn School District
REVIEW SECTION 7 – RULES OF EXPONENTS
Vocabulary
Base of a power: The number that is used as a factor. For example, 2 is
the base of 32 .
Exponent: In a power, the number that indicates how many times the base
is used as a factor. For example, 3 is the exponent in 32 .
Exponential form: The power of a number written using a base and an
exponent. The expression 32 is the exponential form of2 2 2 .
Note: An exponent goes with the base immediately preceding it unless
parentheses indicate otherwise.
Example 1: 23 means 3y y y 2 is the exponent of the base y.
( )2
3 means 3 3y y y 2 is the exponent of the base 3y.
Product of Powers: When two powers with the same base are multiplied,
add the exponents.
m n m na a a + =
Example 2: 2 5 2 5 7x x x x+ = = Think: x is being used as a
factor a total of 7 times.
Example 3: 2 3 2 3 53 3 3 3+ = =
Example 4: + = = =5 1 5 1 5 66 3 6 3 6 3 18c c c c c c
Power of a Power: When a power is raised to a power, multiply exponents.
( )nm mna a=
Example 5: ( )67 7 6 42x x x= =
Example 6: ( )43 3 4 122 2 2= =
37 Copyright © 2020, North Penn School District
Power of a Product: When a product is raised to a power, raise each factor
to the power and then multiply.
( )m m mab a b=
Example 7: ( ) ( )5 5 5 52 2 32x x x− = − = −
Example 8: ( ) ( ) ( ) ( )3 3 332 5 2 5 6 156 6 216x y x y x y= =
Quotient of Powers: When two powers with the same base are divided,
subtract the exponents.
−
−
=
=
If ,
1If ,
mm n
n
m
n n m
am n a
a
an m
a a
Example 9: 8
8 5 3
5
x x x x x x x x xx x
x x x x x x−• • • • • • •
= = =• • • •
Example 10: 5
8 8 5 3
1 1x
x x x−= =
Example 11: 3 2 2
3
4
16 4
a b a
ab b= −
−
Power of a Quotient: When a quotient is raised to a power, raise the
numerator and the denominator to that power. Then divide and simplify.
m m
m
a a
b b
=
Think: Where are the most factors of x?
How many extra factors?
38 Copyright © 2020, North Penn School District
Remember: An exponent is applied
only to the base immediately preceding
it, unless otherwise indicated by
parentheses.
Remember: An exponent is applied
only to the base immediately preceding
it, unless otherwise indicated by
parentheses.
Example 12: ( ) ( )
5 5
5 54 204 5 4
2 2 32 32
3 2433 3x xx x
= = =
Zero Exponents: If a is a real number not equal to zero, then 0 1a = .
(The expression 00 has no meaning!)
Example 13: 025 1=
Example 14: 05 5 1 5x = =
but ( ) ( )( )0 0 05 5 1x x= =
Negative Exponents: If a is a nonzero real number and n is a positive
integer, then 1n
na
a− = . Negative exponents mean reciprocals! All rules for
positive exponents also hold for negative exponents.
Example 15: 3
3
1 12
2 8− = =
Example 16: ( ) ( ) ( )− − −− = =2 1 21 2x x x
Example 17: ( ) ( )4 42 4 2 8
8
162 2 16x x x
x− − −= = =
Example 18: 9
9 2 11
2
xx x x
x −= =
Example 19: − −= = =5
5 12 7
12 7
1xx x
x x
Example 20: ( )− −
−= =
5 3)58
3
4 42
2 2
x xx
x
Note: Simplified expressions must
Note: Negative exponents do not mean
negative numbers!
39 Copyright © 2020, North Penn School District
only have positive exponents.
REVIEW SECTION 8 – OPERATIONS WITH POLYNOMIALS
Vocabulary
Monomial: An expression that is either a numeral, a variable, or the product
of a numeral and one or more variables. Also called terms.
Examples: 13, m, 8c, 2xy, 25p q
Coefficient: In a monomial, the number preceding the variable. When a
monomial does not have a written coefficient, its coefficient is 1.
Polynomial: A sum of monomials. Example: 2 23 2x x y+ + −
Binomial: A polynomial that has exactly two terms. Example: 2 5x +
Trinomial: A polynomial that has three terms. Example: 2 22a ab b− +
Similar or Like Terms: Two monomials that have exactly the same variable
names. Examples: 2 23 and 7 , 5 and xy xy ab ab−
Addition of Polynomials: To add two or more polynomials, combine the
coefficients of the like-terms.
Example 1: ( ) ( )2 2 2 2 2 22 5 6 8 6 10 11 5x xy y x xy y x xy y+ − + + + = + −
Subtraction of Polynomials: To subtract polynomials, change the second
polynomial to its opposite and then add to the first polynomial.
Example 2: ( ) ( )2 2 2 23 6 2 5 5 6 3x xy y x xy y− − − − − + + − =
40 Copyright © 2020, North Penn School District
( ) ( )2 2 2 23 6 2 5 5 6 3x xy y x xy y− − − + − − + = 2 24 11 8 2x xy y− − −
Multiply a Polynomial by a Monomial: Multiply each term of the polynomial
by the monomial, apply the rules for exponents as appropriate.
Example 3: ( )2 3 22 3 2 1 6 4 2x x x x x x− − + = − + −
Multiply a Binomial by a Binomial: Multiply each term of the first binomial
by each term of the second binomial using the distributive property. “FOIL”
(First times First, Outer product, Inner Product, Last times Last)
( )( )a b c d+ +
Example 4:
Example 5:
Example 6:
F
O I
L
( )( )2
2
3 2 2 5 3 2 3 5 ( 2) 2 2 (5)
6 15 4 10
6 11 10
x x x x x x
x x x
x x
− + = + + − −
= + − −
= + −
( )2
2
4 ( 4)( 4)
( )( ) 4 4 (4)(4)
8 16
x x x
x x x x
x x
+ = + +
= + + +
= + +
( )2
2
5 2 (5 2)(5 2)
(5 )(5 ) 2(5 ) 2(5 ) ( 2)( 2)
25 20 4
x x x
x x x x
x x
− = − −
= − − + − −
= − +
41 Copyright © 2020, North Penn School District
REVIEW SECTION 9 – FACTORING POLYNOMIALS
When a polynomial contains only one variable, the degree of a polynomial is
the highest exponent on x.
Factoring polynomials – to write a polynomial as the multiplication of
polynomials of lower degree.
A polynomial that has coefficients that are integers and whose greatest
common factor is 1 is called a prime polynomial. A polynomial is factored
completely when each polynomial factor is prime.
Guidelines for Factoring
1) Factor out the greatest common factor, GCF, first! The greatest
common factor is the greatest factor common to every term in the
polynomial. For variable terms, use the greatest exponent common to
every term in the polynomial.
Example 1: The greatest monomial factor of 5 36 4 8 is 2x x x x− +
since ( )5 3 4 26 4 8 2 3 2 4x x x x x x− + = − + .
2) Look for special patterns:
Difference of Squares: ( )( )2 2a b a b a b− = − +
To factor, take the square root of each term and put one “+” and one
“-“ sign between the terms.
Example 2: ( )( )225 121 5 11 5 11x x x− = − +
3) General Method of Factoring:
For 2x bx c+ + , find two factors of c whose sum is b.
Example 3a: ( )( )2 6 8 2 4x x x x+ + = + + since 2(4) = 8 and 2 + 4 = 6.
Note the following factoring patterns:
when b is positive: ( )( )? ?x x+ +
If c is positive
when b is negative: ( )( )? ?x x− −
42 Copyright © 2020, North Penn School District
If c is negative: ( )( )? ?x x− +
REVIEW SECTION 10- RADICAL EXPRESSIONS
Radical Expression: An expression of the form a . The symbol, , is
called a radical sign and the expression under the radical sign, “a”, is called
the radicand.
Square root: If 2a b= , then a is a square root of b.
(Note: Negative numbers do not have square roots in the set of real
numbers.)
Symbols:
64 8= indicates the nonnegative or principal square root of 64
64 8− = − indicates the negative square root of 64
64 8 = indicates both square roots of 64
I. Simplifying Radicals: To simplify a radical expression, find the square
root of any factors of the radicand that are perfect squares. (If you cannot
see any squares, you can use prime factorization of the radicand.)
Product Property of Square Roots
For any nonnegative real numbers a and b:
ab a b= Example: 4 9 4 9 =
Quotient Property of Square Roots
For any nonnegative real number a and any positive real number b:
a a
b b= Example:
36 36
4 4=
Example 1: 256 4 64 4 64 2 8 16= = = =
Example 2: 50 25 2 25 2 5 2 5 2= = = =
Example 3: 2 80 2 16 5 2 4 5 8 5= = =
43 Copyright © 2020, North Penn School District
Example 4: 169 169 13
100 10100
= =
II. Multiplying Radicals:
Example 5: 4 2 3 4 2 3 4 6 = =
Example 6: 2 3 3 48 2 3 3 48 6 144 6 12 72 = = = =
III. Dividing Radicals:
Example 7: 7 54 7 54 9 3
6 28 6 28 4 2 = = =
Example 8: 24 33 24 33
36 611 2 11 2
= = =
IV. Rationalizing Denominators: A radical is not considered to be in simplest
form if there is a fraction under the radical sign or a radical in the
denominator. Rationalizing is the process of eliminating a radical from the
denominator. (Remember: ( )2
a a= ).
Example 9: 1 1 1 3 3
3 33 3 3
= = =
Example 10: 5 5 2 5 2
22 2 2
= =
V. Adding and Subtracting Radicals: Only radicals with like radicands can be
combined.
Example 11: 8 18 4 2 9 2 2 2 3 2 5 2+ = + = + =
Example 12: 6 24 6 4 6 6 2 6 6− = − = − = −