1. Objective: Solve equations that involve more than one operation. 7-2 Solving Two-Step Equations

2. 5-Minute Check 1.Rupesh earned some money mowing lawns one month. He put half of his money into savings. With the rest, he spent $15 on a new CD, $6 to see a movie, $3 on food, and he still had $24 left. How much money did Rupesh earn mowing lawns that month?

3. 5-Minute Check 1.Rupesh earned some money mowing lawns one month. He put half of his money into savings. With the rest, he spent $15 on a new CD, $6 to see a movie, $3 on food, and he still had $24 left. How much money did Rupesh earn mowing lawns that month? $96

4. 7-2 Solving Two-Step Equations To solve two-step equations, first undo operations involving numbers without variables.

5. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution.

6. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 Add 8 to each side.

7. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 b/2 = 28 Add 8 to each side.

8. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 b/2 = 28 2* b/2 = 28 * 2 Add 8 to each side. Multiply each side by 2.

9. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 b/2 = 28 2* b/2 = 28 * 2 b = 56 Add 8 to each side. Multiply each side by 2.

10. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 b/2 = 28 2* b/2 = 28 * 2 b = 56 Check: b/2 – 8 = 20 Add 8 to each side. Multiply each side by 2.

11. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 b/2 = 28 2* b/2 = 28 * 2 b = 56 Check: b/2 – 8 = 20 56/2 – 8 ?= 20 Add 8 to each side. Multiply each side by 2. Replace b with 56.

12. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 b/2 = 28 2* b/2 = 28 * 2 b = 56 Check: b/2 – 8 = 20 56/2 – 8 ?= 20 28 – 8 ?= 20 Add 8 to each side. Multiply each side by 2. Replace b with 56. Do the division first.

13. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 b/2 = 28 2* b/2 = 28 * 2 b = 56 Check: b/2 – 8 = 20 56/2 – 8 ?= 20 28 – 8 ?= 20 20 ?= 20 Add 8 to each side. Multiply each side by 2. Replace b with 56. Do the division first. The solution is 56.

14. 7-2 Solving Two-Step Equations Example Solve b/2 – 8 = 20. Check your solution. b/2 – 8 = 20 b/2 – 8 + 8 = 20 + 8 b/2 = 28 2* b/2 = 28 * 2 b = 56 Check: b/2 – 8 = 20 56/2 – 8 ?= 20 28 – 8 ?= 20 20 ?= 20 Add 8 to each side. Multiply each side by 2. Replace b with 56. Do the division first. The solution is 56.

15. SOLVE ON YOUR OWN 12b – 7 = 137

16. COMBINING LIKE TERMS 4m + 2m – 7 = 23 combine like terms first 4m + 2m 6m - 7 = 23 add 7 to both sides + 7 = +7 6m = 30 divide both sides by 6 / 6 / 6 m = 5

17. COMBINE ON YOUR OWN 7m – 4 + 2m +7 = 30

18. VARIABLES IN BOTH SIDES 5s + 2 = 10 + 1s move all the variables in one side -1s -1s 4s + 2 = 10 subtract 2 from both sides - 2 -2 4s = 8 divide both sides by 4 /4 /4 s = 2

19. SOLVE ON YOUR OWN 6b + 9 = 3b + 12