1. One-Step Equations with Addition and Subtraction
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2. Warm Up Evaluate the expression. 5a + 6b – 8 if a = 4 and b=-2
6x – 2(x + 9) if x = -4
-5a + 2 if a = 5
3x – x + 6y if x =7 and y= -1
-34
- 23 8

3. One-Step Equations with Addition and Subtraction

5. You use the subtraction property of equality to subtract 2 from both sides in order to get the “y” by itself.
2 -2
x = 2
Ck: = 4
√4= 4
To check to see if your answer is correct, substitute the x in your equation with the 2. Solve the equation. If it is true then the value for x is correct.

6. You use the addition property of equality to add 6 to both sides in order to get the “y” by itself.
x = 16
Ck: 16-6=10
√10=10
To check to see if your answer is correct, substitute the x in your equation with the 16. Solve the equation. If it is true then the value for x is correct

7. Practice
x + 10 = 23
a – 7 = - 87
6 + y = -23
-12 + m = 34
x = 13
a = - 80
y = - 29
m = 46

8. Explain how to solve x – 138 = 245.
Closure
Explain how to solve x – 138 = 245.