CRCT Domain Review

Algebra

Key VocabularyEquivalentEqual to

EvaluateTo calculate the value of or

substitute given values in for variables

SimplifyTo make smallerExpressions= Combine Like

TermsFractions= Lowest Terms

Key Vocabulary

ConstantThe value that does not change

CoefficientThe number attached to the

variable

Like TermsTerms that contain the same

variable(s) raised to the same power(s)

SubstitutionPutting in a value for a given

variable

Write Expressions and Equations

ExpressionsDO NOT have an equal sign and have various answers depending on the values given

EquationsDO have an EQUAL sign and

one answer for the variable

Write Expressions and Equations

Example: ExpressionWhich expression represents

the phrase below.83 less than a number n

a)83 – nb)n – 83c)83 ÷ nd)n ÷ 83

Write Expressions and Equations

Example: Equation

Lou had r rocks in his collection. He separated his rocks into 3 piles. He now has 12 rocks in each pile. Which equation represents this situation?

a) r-3 = 12

b) r ÷ 3 = 12

c) r + 3 = 12

d) r x 3 = 12

Percent of a NumberChange percent to a decimal and

multiply by the numberOr

Use =

Commission- what is earned from the original

Tax, tip, interest, mark-up- Add this amount to the originalOriginal + tip = total due

Discount, markdown, coupon, % off- Subtract this amount from the originalOriginal – discount = sale price

Percent ChangeWhen an amount changes, it is sometimes helpful to find the “percent change”.

This can be a “percent increase” if the amount went up, or a “percent decrease” if the amount went down. Both are calculated the same way:

What is the percent change from 20 to 29?

Solving EquationsFinding the value of a variable in an equation or solving a word problem.

Solve using inverse operations.

What is done on one side, must be done on the other.

Solving EquationsExample:Justin is 10 years less than half his father’s age. If Justin is 12 years old, how old is his father?

a) 22b) 24c) 32d) 44

Solving EquationsExample:

Marissa bought 3 sweaters on sale for the same price. After using a coupon for $25, the total cost was $80.

Write an algebraic equation AND solve to find the cost of each sweater.

Simplifying Expressions

Combine Like Terms

Use sign in FRONT of the number

Clear parenthesis

Cannot combine different variables or different powers

EX. Simplify the following:

2x + 3y + 4x2 + 5y

Simplifying ExpressionsSimplify

3 + 5r – (2r – 5)

a) 3r – 2

b) 3r + 8

c) 8r – 3

d) 8r +3

Simplifying ExpressionsSimplify

8x + 4x + y + 3y

a) 3(4x + y)

b) 4(3x + y)

c) 2(6x + y)

d) 2(6x + 2y)

Translating Phrases (equations)

Use the operational vocabulary to indicate what operation(s) will be required for the equation.

Will have an equal sign

Solve using inverse operations

Translating Phrases (equations)

This season, the number of points Reggie scores was 36 less than 4 times the number Larry scored. Reggie scored 64 points this season. The equation below represents this situation.

4n – 36 = 64

What does n represent in the equation?

a) the number of points Reggie scored

b) the number of points Larry scored

c) how many more points Reggie scored than Larry

d) how many points Reggie and Larry scored in all

Inverse OperationsDo UnDo

Addition Subtraction

Multiplication

Division

Examples: 3g – 7 = 14 m/3 + 5 = 13