1. One-Step Equations with Subtraction

2. Warm Up Evaluate the expression. 4a + 7b – 8 if a = 4 and b=2
15x – 2(x + 9) if x = 2
5a + 4 if a = 6
3x – x + 5y if x =5 and y= 1 22 8 34 15

3. One-Step Equations with Subtraction

5. +2 +2 x = 8 Review Example 1: x - 2 = 6
x = 8
You use the addition property of equality to add 2 to both sides in order to get the “x” by itself.
To check to see if your answer is correct, substitute 8 in the place of x in your equation. Solve the equation. If it is true then the value for x is correct.

6. Ex. 2: y – 6 = 12
You use the addition property of equality to add 6 to both sides in order to get the “y” by itself.
y = 18
To check to see if your answer is correct, substitute 18 in the place of y in your equation. Solve the equation. If it is true then the value for y is correct

7. Practice
x - 9 = 24
a – 6 = 86
y - 5 = 24
m - 13 = 33
x = 33
a = 92
y = 29
m = 46

8. Closure
Explain how to solve
x – 23 = 243.