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3. Solving Two – Step Equations Determine the mathematical operations being performed on the variable. 2x + 5 = − 15 Addition of 5 Undo the operations using inverse operations. Multiplication of 2

4. Solving Two – Step Equations 2x + 5 = − 15 Undo any addition or subtraction: 2x + 5 = − 15 − 5 Operations must be performed on both sides of equal sign Simplify each side of equal sign − 202x + 0 2x− 20 =

5. Solving Two – Step Equations 2x = − 20 Undo any multiplication or division 2x = − 2 0 ___ Operations must be performed on both sides of equal sign Simplify each side of equal sign − 101x x− 10 = ___ 2 2 (Continued)

6. Solving Two – Step Equations 2x + 5 = − 15 Check your solution for accuracy: x = − 10 Simplify the left side of the equal sign. Substitute ̶ 10 for x. − 15 − 20 = Solution: + 5 = − 152x + 5 − 15 The check was successful-- Original Equation: 2(− 10) =

7. Solving Two – Step Equations − 8 = − 10 Add 8 to both sides Simplify each side of equal sign = − 2 + 8 Multiply by 4 4 4 Simplify each side of equal sign x = − 8 x = − 8 Solve: 4x 4x

8. Solving Two – Step Equations Add 19 to both sides Divide by − 7 _______ _______ − 7 − 7 Simplify Solve: Simplify each side of equal sign

9. Solving Two – Step Equations Add 4 to both sides Multiply by − 10 Simplify Solve: (− 10) Simplify each side of equal sign

10. Solving Two – Step Equations Determine the mathematical operations being performed on the variable. Undo the operations using inverse operations. SUMMARY Perform the inverse operation on both sides of the equation.