1-3 ORDER OF

OPERATIONS

M S . BA T T A G L I A

– A

L G E B R A 1 C

P

O B J EC T I V

E : US E T

H E OR D E R O

F OP E R A T I O

N S

A N D EV A L U A T E V

A R I AB L E E

X P R E S S I ON S .

WARM UPCompare the quantities in Column A and

Column B.Column

AColumn

BThe total cost of items bought by a customer

The change the customer receives when paying with a $10 bill.

A.The quantity in Column A is greater.

B.The quantity in Column B is greater.

C.The quantities are equal.

D.The relationship cannot be determined from the information given.

1-2 HOMEWORK SOLUTIONSP. 13-14 #2, 4, 6, 8, 10, 14, 16, 20, 21, 22, 30, 31

2) 4 16) s=½e 4) 1 20) a) yes 3x2=66) A letter that represents b) yes 3+3=6a number. 21) b) 1 lawn: 2 hours8) p=perimeter, s=side; p=4s 2 lawns: 4 hours 10) n=number of slices left, 5 lawns: 10 hourse=number of slices eaten; 22) a) f=½d n=8 – e b) 10 ft14) c=8.50t 30) 7 31) 7

WORK WITH A PARTNER…Two formulas for the perimeter of a rectangle

are P = 2l + 2w and P = 2( l + w )

1) Let l = 12 and w = 8. Find the perimeter of the rectangle using each formula.

2) When you used the formula P = 2l + 2w, did you add first or multiply first?

3) When you used the formula P = 2 (l + w), did you add first or multiply first?

4) Which formula do you prefer to use? Why?

DISCOVER…Solve 3 + 5 – 6 ÷ 2 Solve 3 + 5 – 6 ÷ 2

using division from left to right. then addition, then

subtraction.

ORDER OF OPERATIONS

From left to right

QUICK REVIEW!!

An exponent indicates repeated multiplication.

34 = 3 3 3 3

EXAMPLEWhich operation should you do first to simplify each expression?

1.3 + 6 4 ÷ 2

2.3 6 – 42

3.3 (6 – 4) ÷ 2

4.3 ÷ 2 6

Find the total cost of the sneakers shown in the ad.

Use p + r ∙ p price sales tax

sales tax rate

Evaluate an expression with

variables by substituting a

number for each variable.

7%

EXAMPLE

Evaluate 3a2 – 12 ÷ b for a = 7 and b = 4

EXAMPLE

Evaluate each expression for c = 3 and d = 2

a) cd2 b) (cd)2

EXAMPLEWrite an expression for each phrase.a) Four times three, squared b) The square of

three, times four

CLASSWORK

Card Matching Game

HOMEWORK

P. 17-18 #2 – 12 even, 18,20,26,28