1. Solve an equation using addition EXAMPLE 2 Solve x – 12 = 3. Horizontal format Vertical format x– 12 = 3 Write original equation. x – 12 = 3 Add 12 to each side. +12 x = 15 Simplify. x = 15 x – 12 + 12 = 3 +12

2. Solve an equation using division EXAMPLE 3 Solve – 6x = 48. – 6x = 48 x = – 8 Write original equation. – 6x– 6x – 6– 6 48 – 6– 6 = Divide each side by – 6. Simplify.

3. GUIDED PRACTICE for Example 2 and 3 1. y + 7 = 10. y + 7 = 10 Write original equation. y + 7 – 7 = 10 – 7 Use subtraction property of equality: Subtract 7 from each side. y = 3y = 3 Simplify. ANSWER The solution is 3. Solve the equation. Check your solution.

4. GUIDED PRACTICE for Example 2 and 3 CHECK Substitute 3 for y in the original equation. y + 7 = 10 Write original equation. 3 + 7 = 10 ? Substitute 3 for y. 10 = 10 Simplify. Solution checks.

5. 2. x – 5 = 3. Horizontal format Vertical format x – 5 = 3x – 5 = 3 Write original equation. x – 5 = 3 Add 5 to each side. +5+5+5+5 x = 8 Simplify. x = 8 x – 5 + 5 = 3 +5 GUIDED PRACTICE for Example 2 and 3 Solve the equation. Check your solution.

6. GUIDED PRACTICE for Example 2 and 3 CHECK Substitute 8 for x in the original equation. x – 5 = 3x – 5 = 3 Write original equation. 8 – 5 = 3 ? Substitute 8 for x. 3 = 3 Simplify. Solution checks.

7. GUIDED PRACTICE for Example 2 and 3 3. q – 11 = – 5. Horizontal format Vertical format q – 11 = – 5 Write original equation. q – 11 = – 5 Add 11 to each side. q = 6 Simplify. q = 6 q – 11 + 11 = – 5 +11 +11– 11 Solve the equation. Check your solution.

8. GUIDED PRACTICE for Example 2 and 3 CHECK Substitute 6 for q in the original equation. q – 11 = –5 Write original equation. 6 – 11 = –5 ? Substitute 6 for q. –5 = –5 Simplify. Solution checks.

9. GUIDED PRACTICE for Example 2 and 3 4. 6 = t – 2. Horizontal format Vertical format 6 = t – 2 Write original equation. 6 = t – 2 Add 2 to each side. + 2 8 = t Simplify. 8 = t 6 + 2 = t – 2 + 2 Solve the equation. Check your solution.

10. GUIDED PRACTICE for Example 2 and 3 CHECK Substitute 8 for t in the original equation. 6 = t – 2 Write original equation. 6 = 8 – 2 ? Substitute 8 for t. 6 = 6 Simplify. Solution checks.

11. GUIDED PRACTICE for Example 2 and 3 5. 4x = 48. 4x = 48 x = 12 Write original equation. 4x 4x 4 48 4 = Divide each side by 4. Simplify. Solve the equation. Check your solution.

12. GUIDED PRACTICE for Example 2 and 3 CHECK Substitute 12 for x in the original equation. 4x = 48. Write original equation. Substitute 12 for x. 48 = 48 Simplify. Solution checks. 4 12 = 48 ?

13. GUIDED PRACTICE for Example 2 and 3 6. – 65 = – 5y. – 65 = – 5y 13 = y Write original equation. – 65 – 5 – 5y – 5 = Divide each side by – 5s Simplify. Solve the equation. Check your solution.

14. GUIDED PRACTICE for Example 2 and 3 CHECK Substitute 13 for y in the original equation. – 65 = – 5y Write original equation. Substitute 13 for y. – 65 = – 65 Simplify. Solution checks. – 65 = – 5 ? 13

15. GUIDED PRACTICE for Example 2 and 3 7. 6w = – 54. 6w = – 54 w = – 9 Write original equation. 6w 6 – 54 6 = Divide each side by 6. Simplify. Solve the equation. Check your solution.

16. GUIDED PRACTICE for Example 2 and 3 CHECK Substitute 9 for w in the original equation. 6w = – 54 Write original equation. Substitute – 9 for w. – 54 = – 54 Simplify. Solution checks. 6 – 9 = – 54 ?

17. GUIDED PRACTICE for Example 2 and 3 8. 24 = – 8n. 24 = – 8n – 3 = n Write original equation. 24 – 8 – 8n – 8 = Divide each side by – 8. Simplify. Solve the equation. Check your solution.

18. GUIDED PRACTICE for Example 2 and 3 CHECK Substitute – 3 for n in the original equation. 24 = – 8n Write original equation. Substitute – 3 for n. 24 = 24 Simplify. Solution checks. 24 = – 8 ? – 3