Two Step EquationsStep One: Add or Subtract on

both sidesStep Two: Multiply or Divide on

both sides.

in-class practice itemsFor chapter 3.3

following steps

• Find the variable.• What is the

operation?• Use the inverse

operation on both sides

• Work down.

• r + 18 = - 7• r + 18 = - 7• r + 18 = - 7• - 18 -18• r + 0 = -25• r = -25

following steps

• Find the variable.• What is the

operation?• Use the inverse

operation on both sides

• Work down.

• 6.3r = - 7• 6.3r = - 7• 6.3r = - 7• 6.3 6.3• 1r = -1.1• r = -1.1

1

Order of two-step equations.

• Isolate the variable that is attached by division or multiplication.

• Use the inverse operation on both sides

• Work down.• Isolate the variable.

7x - 5 = -54

+5 +5

7x + 0 = -49

7x = -49

7 7

1x = - 7

x = - 7

1

Practice the order

• 5x+9=39

• 9p+11 = -7

• 3 + 2x = 21

• 12 = 9x - 6

• -8m – 12 = 20

• 8p + 15 = 87

• 47 = 2f – 3

• 16 = -5w - 9

Practice the steps

• 5x+9=39 • -8m – 12 = 20

Practice answers

• 5x+9=39 • -8m – 12 = 20

5 9 9 39 9x 5 30

5 5

x

6x

8 12 12 20 12m

8 32m 8 32

8 8

m

4m

Practice the equations

9p+11 = -7 • 8p + 15 = 87

Practice answers

9p+11 = -7 • 8p + 15 = 87

9 11 11 7 11p

9 18

9 9

p

2p

8 15 15 87 15p

8 72

8 8

p

9p

What’s the order?

22 205

z 3.2 1.4

5

x

1 31

10

d

Add 22, then multiply by 5

Subtract 3.2, then multiply by -5

Add 1, then multiply by 10

Work the Steps

22 205

z 3.2 1.4

5

x

1 31

10

d

Work the Steps

0 25

z

52 5

1 5

z

22 205

z 3.2 1.4

5

x

1 31

10

d

+22+22

510

5

z

10z

-3.2-3.2

1.85

x

5

1.8 55

x

1 9x

9x

+1+1

1030 10

1 10

d

10300

10

d

1 300d 300d