One-Step Equations with Addition and Subtraction TeacherTwins©2014

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

One-Step Equations with Addition and Subtraction

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: 2 + 2 = 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.

You use the addition property of equality to add 6 to both sides in order to get the “y” by itself. +6 +6 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

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

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