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Course 1
1-3 Exponents1-3 Exponents
Course 1
Warm UpWarm Up
Lesson PresentationLesson Presentation
Problem of the DayProblem of the Day
Course 1
1-3 Exponents
Problem of the Day
Replace the letters a, b, and c with the numbers 3, 4, and 5 to make a true statement.2a + 2a = bc
25+ 25 = 43
Course 1
1-3 Exponents
A number is in exponential form when it is written with a base and an exponent.
7733Base
Exponent
= 7 7 7= 343
An exponent tells how many times a number called the base is used as a factor.
Course 1
1-3 Exponents
Exponential Form 102
Read“10 squared” or “10 to the 2nd power”
Multiply 10 10
Value 100
Course 1
1-3 Exponents
Exponential Form 103
Read“10 cubed” or “10 to the 3rd power”
Multiply 10 10 10
Value 1,000
Course 1
1-3 Exponents
Exponential Form 104
Read “10 to the 4th power”
Multiply 10 10 10 10
Value 10,000
Course 1
1-3 Exponents
Additional Example 1: Writing Numbers in Exponential Form
Write each expression in exponential form.
A. 5 5 5 5
B. 3 3 3 3 3
5 is a factor 4 times.54
3 is a factor 5 times.35
Course 1
1-3 Exponents
Check It Out: Example 1
Write each expression in exponential form.
A. 7 7 7
B. 6 6 6 6 6 6
7 is a factor 3 times.73
6 is a factor 6 times.66
Course 1
1-3 Exponents
Additional Example 2: Finding the Value of Numbers in Exponential Form
Find each value.
A. 26
B. 45
26
45
= 2 2 2 2 2 2
= 64
= 4 4 4 4 4
= 1,024
Course 1
1-3 Exponents
Check It Out: Example 2
Find each value.
A. 34
B. 25
34
25
= 3 3 3 3
= 81
= 2 2 2 2 2
= 32
Course 1
1-3 Exponents
A phone tree is used to contact families at Paul’s school. The secretary calls 4 families. Then each family calls 4 other families, and so on. How many families will be notified during the fourth round of calls?
11 Understand the Problem
The answer will be the number of families called in the 4th round.
List the important information:
• The secretary calls 4 families.
• Each family calls 4 families.
Additional Example 3: Problem Solving Application
Course 1
1-3 Exponents
You can draw a diagram to see how many calls are in each round.
22 Make a Plan
Secretary
1st round – 4 calls
2nd round–16 calls
Course 1
1-3 Exponents
Solve33Notice that in each round, the number of calls is a power of 4.
1st round: 4 calls = 4 = 41
2nd round: 16 calls = 4 4 = 42
So during the 4th round, there will be 44 calls. 44 = 4 4 4 4 = 256
During the 4th round of calls, 256 families will have been notified.
Look Back44Drawing a diagram helps you see how to use exponents to solve the problem.
Course 1
1-3 Exponents
Check It Out: Example 3
A phone tree is used to contact families at Paul’s school. The secretary calls 3 families. Then each family calls 3 other families, and so on. How many families will be notified during the fourth round of calls?
11 Understand the Problem
The answer will be the number of families called in the 4th round.
List the important information:
• The secretary calls 3 families.
• Each family calls 3 families.
Course 1
1-3 Exponents
You can draw a diagram to see how many calls are in each round.
22 Make a Plan
Secretary
1st round – 3 calls
2nd round–9 calls
Course 1
1-3 Exponents
Solve33Notice that in each round, the number of calls is a power of 3.
1st round: 3 calls = 3 = 31
2nd round: 9 calls = 3 x 3 = 32
So during the 4th round, there will be 34 calls. 34 = 3 3 3 3 = 81
During the 4th round of calls, 81 families will have been notified.
Look Back44Drawing a diagram helps you see how to use exponents to solve the problem.
Course 1
1-3 Exponents
Lesson Quiz
Write each expression in exponential form.
1. 12 12 12
2. 9 9 9 9 9 9 9
Find each value.
3. 202 4. 64
5. In a phone tree, each of three people will call
three people, and then each of those will call
three more. If there are five levels of the tree,
how many people will be called?
97
123
400 1,296
243
Course 1
1-3 Exponents1-4 Order of Operations
Course 1
Warm UpWarm Up
Lesson PresentationLesson Presentation
Problem of the DayProblem of the Day
Course 1
1-3 Exponents
Warm UpPerform the operations in order from left to right.
1. 8 + 4 – 22. 9 3 + 13. 7 – 3 + 54. 20 ÷ 4 + 6
10
289
11
Course 1
1-3 Exponents
Problem of the Day
0 1 2 3 4 5 6 7 8 9 = 1Put the appropriate plus or minus signs between the numbers so that the total equals 1.
0 + 1 – 23 + 45 + 67 – 89 = 1
Course 1
1-3 Exponents
A numerical expression is a mathematical phrase that includes only numbers and operation symbols.
Numerical Expressions
4 + 8 ÷ 2 6
371 – 203 + 2 5,006 19
When you evaluate a numerical expression, you find its value.
Course 1
1-3 Exponents
When an expression has more than one operation, you must know which operation to do first. To make sure that everyone gets the same answer, we use the order of operations.
ORDER OF OPERATIONS1. Perform operations in parentheses.2. Find the values of numbers with exponents.3. Multiply or divide from left to right as ordered in the problem.4. Add or subtract from left to right as ordered in the problem.
Course 1
1-3 Exponents
The first letters of these words can help you remember the order of operations.
Please Parentheses
Excuse Exponents
My Multiply
Dear Divide
Aunt Add
Sally Subtract
Helpful Hint
Course 1
1-3 Exponents
Additional Example 1A: Using the Order of Operations
Evaluate the expression.
There are no parentheses or exponents.
15 – 5 Divide.
10 Subtract.
15 – 10 ÷ 2
15 – 10 ÷ 2
Course 1
1-3 Exponents
Additional Example 1B: Using the Order of Operations
Evaluate the expression.
9 + (21 ÷ 7) 5
9 + (21 ÷ 7) 5
Perform operations within parentheses.
Multiply.
9 + 3 5
9 + 15
Add. 24
Course 1
1-3 Exponents
Check It Out: Example 1A
Evaluate the expression.
There are no parentheses or exponents.
12 – 3 Divide.
9 Subtract.
12 – 6 ÷ 2
12 – 6 ÷ 2
Course 1
1-3 Exponents
Check It Out: Example 1B
Evaluate the expression.
7 + (24 ÷ 6) 3
7 + (24 ÷ 6) 3
Perform operations within parentheses.
Multiply.
7 + 4 3
7 + 12
Add. 19
Course 1
1-3 Exponents
Additional Example 2A: Using the Order of Operations with Exponents
Evaluate the expression.
24 + 6 4
There are no parentheses.
Multiply.
16 + 6 4
16 + 24
Add. 40
2 + 6 4 4
Find the value of the number with the exponent.
Course 1
1-3 Exponents
Additional Example 2B: Using the Order of Operations with Exponents
Evaluate the expression.
24 ÷ (9 – 6) 32 – 10
Perform operations within parentheses.
Multiply.
8 9 – 10
72 – 10
Divide.
62
Find the value of the number with the exponent.
24 ÷ (9 – 6) 32 – 10
24 ÷ 3 32 – 10
24 ÷ 3 9 – 10
Subtract.
Course 1
1-3 Exponents
Check It Out: Example 2A
Evaluate the expression.
42 + 3 7
There are no parentheses.
Multiply.
16 + 3 7
16 + 21
Add. 37
42 + 3 7
Find the value of the number with the exponent.
Course 1
1-3 Exponents
Check It Out: Example 2B
Evaluate the expression.
32 ÷ (8 – 4) 22 – 12
Perform operations within parentheses.
Multiply.
8 4 – 12
32 – 12
Divide.
20
Find the value of the number with the exponent.
32 ÷ (8 – 4) 22 – 12
32 ÷ 4 22 – 12
32 ÷ 4 4 – 12
Subtract.
Course 1
1-3 Exponents
Additional Example 3: Consumer Application
Mr. Kellett bought 6 used CDs for $4 each and 5 used CDs for $3 each. Evaluate the following expression to find the amount Mr. Kellett spent on CDs.
6 4 + 5 3
24 + 15
39
Mr. Kellett spent $39 on CDs.
Course 1
1-3 Exponents
Check It Out: Example 3
Ms. Nivia bought 4 new CDs for $8 each and 6 used CDs for $4 each. Evaluate the following expression to find the amount Ms. Nivia spent on CDs.
4 8 + 6 4
32 + 24
56
Ms. Nivia spent $56 on CDs.