1. Objective 23 Solve two-step equations ©2002 by R. Villar All Rights Reserved

2. Solve two-step equations How do you solve for a variable when there are more than one operation? Since we are “undoing” the problem, we will do PEMDAS in reverse order... Example 7y – 2 = 19 +2 +2 undo addition/subtraction first 7y = 21 7y = 21 undo multiplication/division last 7 7 y = 3 Be sure to check your solution 7(3) – 2 = 19 21 – 2 = 19 √

3. Example: Undo the subtraction first... +8 +8 Now, multiply by the reciprocal... 1 2 x = 14 Check: √

4. Example: Don’t forget that you will need a common denominator (only for the addition part of the problem)... What is the common denominator for 12 and 2? 12 6 Now, multiply by the reciprocal... 2 1 x = – 7 10