1. SOLVING ONE-STEP EQUATIONS
DAY TWO
Ms. Turk, Algebra I
Unit 2-1

2. Solving One-Step Equations With Multiplication & Division
Multiplication and division are inverse operations. In other words, they undo each other. When you solve an equation involving division, multiply each side of the equation by the same number.

3. Example 1: Multiplication
(-4) (-4)
x = 45.6
Multiply each side of the equation by -4 in order to isolate the variable on one side of the equation.
Simplify.

4. Example 2: Multiplication
(10) (10)
x = 34
Multiply each side of the equation by 10 to get the variable on one side of the equation.
Simplify.

5. Example 3: Multiplication
Try one on your own!
(12) (12)
m = 30
Did you multiply both sides by 12?
Then did you simplify?

6. Example 4: Division 5x = 35 5x ÷ 5 = 35 ÷ 5 x = 7
Divide both sides of the equation by 5 to isolate the variable on one side.
Simplify.
x = 7

7. Example 5: Division 10x = 125 10x ÷ 10 = 125 ÷ 10
Divide both sides by 10 to get x by itself on one side of the equation.
Simplify.
x = 12.5

8. Example 6: Division 6.5x = 195 6.5x ÷ 6.5 = 195 ÷ 6.5
Try one on your own!
6.5x = 195
6.5x ÷ 6.5 = 195 ÷ 6.5
Did you divide both sides by 6.5?
Then did you simplify?
x = 30

9. Real World Problem Solving
Wages
Suppose you work part-time at the city library. You earn $ for 19 hours of work. What is your hourly wage? Write and solve an algebraic equation to solve this problem.

10. Real World Problem Solving
Relate:
Define:
Write:
Number of hours worked times
wage equals total earnings.
Let w = wage.
19 w =

11. Real World Problem Solving
w = 7.65
Your hourly wage is $7.65.

12. Now you try!
Car Repair
Your bill for car repair is $ One third of the bill is for labor. Write and solve an equation to solve for the cost of labor.

13. Now you try!
The repair bill divided by three equals the cost of labor.
Let c = cost of labor
321 = c 3
Relate:
Define:
Write:

14. Now you try!
321 = c 3
c = 107
The cost of labor is $107.00

15. Practice Problems
Please take a few moments to complete the following practice problems in your notes.
2x = 17
18x = 70
x/2 = 100
x/3.5 = 12
4.2x = 20
(8.5)
(3.89)
(200)
(42)
(4.76)

16. A. Workbook page 20 22, 25, 27 - 50 all B. Square Deal Game
Classwork
A. Workbook page 20
22, 25, all
B. Square Deal Game