1. 1.2 Algebraic Expressions 8/23/13

2. x3 Vocabulary Variable: A letter used to represent one or more numbers
Exponent: The number or variable that represents the
number of times the base of a power is used as a
factor
Power: An expression that represents repeated
multiplication of the same factor
Base: The number used as a factor in a repeated
multiplication x3

3. What’s the difference? Example 1 – 2 • = ( ) – 16 = – ) 4 ( 2 – • ( 2
Evaluate Powers a. – 24 2 • = ( ) –
Multiply 2 to itself 4 times 16 = –
Make the answer negative. b.
) 4 ( 2 – • ( 2 – ) =
Multiply -2 to itself 4 times. = 16
What’s the difference? 3

4. 1. 43 ) 2 ( 3 – 3. 33 – – 21 Checkpoint Evaluate Powers
Evaluate the power. 1. 43
ANSWER 64 2.
) 2 ( 3 –
ANSWER 9 3. 33 –
ANSWER 27 – 4. 21
ANSWER 2 4

5. Order of Operations
Step 1: Perform operations that occur within grouping symbols.
Brackets [ ] Parenthesis ( )
Step 2: Evaluate powers (exponents).
Step 3: Perform multiplications and divisions from left to right .
Step 4: Perform additions and subtractions from left to right.

6. Example 2 36 ÷ 4 • ( – 1 + 4 )2 = 4 36 ÷ • 32 = 4 36 ÷ • 9 = 9 • = 81
Use Order of Operations 36 ÷ 4 • ( – 1 + 4 )2
Evaluate what’s in ( ). = 4 36 ÷ • 32
Evaluate power. = 4 36 ÷ • 9
Divide. = 9 • = 81
Multiply. 6

7. Example 3 ( ) 5 + x 2 7x – = ( ) 5 + x 2 7x – 4 7 = – ( 4 7 ) 9 2 28
Evaluate an Algebraic Expression
Evaluate when x = 4. ( ) 5 + x 2 7x –
Evaluate means to calculate the value of.
SOLUTION
Substitute 4 for x. = ( ) 5 + x 2 7x – 4 7 = – ( 4 7 ) 9 2
Evaluate what’s in ( ). 28 18 =
Multiply. – =
Subtract. 10 – 7

8. [ ] Example 4 4p2 – ( 2p ) 9 = ( 4 4p2 – 2p ) 9 3 )2 2 51 =
Evaluate an Algebraic Expression
Evaluate when p = - 3.
4p2 – ( 2p ) 9
SOLUTION
Substitute - 3 for p. = ( 4
4p2 – 2p ) 9 3 )2 [ ] 2
=4 9 − −6−9
=36−(−15) 51 = 8

9. Checkpoint
Evaluate Expressions
Evaluate the expression. 5.
ANSWER 12 8 – 3 + 7 6. 2 – 6 + ÷ 4 •
ANSWER 23 7. ( 5 7 3 4 – )2
ANSWER 8 –
Evaluate the expression for the given value of the variable. 8. 3 – + ( 1 y 6 )
when 2 =
ANSWER 15 9

10. Homework 1.2 p.12 #21-53 odd Remember: Pencil Only. Write heading.
Copy problems and show work.
Circle, highlight or box final answer.