VariablesVariables

Chapter 1.2Chapter 1.2

Pages 11-15Pages 11-15

Warm Up ActivityWarm Up Activity

Sasha wanted to leave the Sasha wanted to leave the waiter and 20% tip. The bill for waiter and 20% tip. The bill for the meal was $23.50. How much the meal was $23.50. How much did Sasha leave on the table?did Sasha leave on the table?

A triangle has two sides that are A triangle has two sides that are congruent (equal) in length. congruent (equal) in length. – How many angles are congruent? How many angles are congruent? – Name the triangle.Name the triangle.

First Grade AlgebraFirst Grade Algebra

+ 6 = 16+ 6 = 16

5 + = 95 + = 9

- 5 = 5- 5 = 5

8 - = 28 - = 2

Fill in the missing Fill in the missing box.box.

The BOX was the The BOX was the variable.variable.

What is the What is the variable?variable?

x + 6 = 16x + 6 = 16

5 + t = 95 + t = 9

n - 5 = 5n - 5 = 5

8 - r = 28 - r = 2

Fill in for the variable.Fill in for the variable.John makes $7.00 per John makes $7.00 per hour (h) but chooses hour (h) but chooses

to pay a uniform to pay a uniform cleaning fee of cleaning fee of

$3.00 each day he $3.00 each day he works. How much works. How much

does he make each does he make each day?day? … …

$7(h) - $3$7(h) - $3Number of Number of

hourshoursCalculationCalculation Day’s PayDay’s Pay

44 7(4) - 37(4) - 3

66 7(6) - 37(6) - 3

88 7(8) - 37(8) - 3

$7(h) - $3$7(h) - $3Number of Number of

hourshoursCalculationCalculation Day’s PayDay’s Pay

44 7(4) - 37(4) - 3 $25$25

66 7(6) - 37(6) - 3 $39$39

88 7(8) - 37(8) - 3 $55$55

Write an expressionWrite an expressionNancee pays $1.50 to Nancee pays $1.50 to

ride the bus each ride the bus each way. She makes $20 way. She makes $20 each night she sits each night she sits

for her young for her young cousin. How much cousin. How much does she make? does she make?

Sometimes she gets Sometimes she gets a ride home for free a ride home for free

from her brother.from her brother.

Let (r) be the number of Let (r) be the number of rides she needs.rides she needs.

r * $1.50 = $3.00r * $1.50 = $3.00

r * $1.50 = $1.50r * $1.50 = $1.50

Subtract bus fare from Subtract bus fare from the total earned…the total earned…

$20 - 1.5r$20 - 1.5rThe order of The order of

operations states, operations states, do the do the

multiplication first, multiplication first, then subtract.then subtract.

Solve for x.Solve for x.Guess and test.Guess and test.

4x + 3 = 474x + 3 = 47

7x – 12 = 447x – 12 = 44

These workThese work

4(11) + 3 = 474(11) + 3 = 47

7(8) – 12 = 447(8) – 12 = 44

Pens cost $.30 Pens cost $.30 Pencils cost $.20Pencils cost $.20

How much for 10 How much for 10 pencils?pencils?

How much for 2 How much for 2 pens and 4 pens and 4

pencils?pencils?

Total BillTotal Bill10 (.20) = $210 (.20) = $2

2(.30) + 4 (.20) =2(.30) + 4 (.20) =(.60) + (.80) =(.60) + (.80) =

$1.40$1.40

Your AssignmentYour AssignmentPage 16 – 17Page 16 – 17

# 11-37, and 45 odds# 11-37, and 45 odds