2-6 Subtraction Equations Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day Lesson Quizzes Lesson Quizzes

2-6 Subtraction Equations Warm Up Solve each equation. 1. x + 7 = x = = x = x + 4 x = 15 x = 87 x = 7 x = 19

2-6 Subtraction Equations Problem of the Day Bruce has 25 CDs remaining after giving 14 to John, 17 to Mary, and 25 to Sue. How many CDs did he begin with? 81

2-6 Subtraction Equations Learn to solve whole-number subtraction equations.

2-6 Subtraction Equations When Theodore Roosevelt became president of the United States, he was 42 years old. He was 27 years younger than Ronald Reagan was when Reagan became president. How old was Reagan when he became president?

2-6 Subtraction Equations Ronald Reagan’s age Theodore Roosevelt’s age – = 27 Let a represent Ronald Reagan’s age. a – = 2742 a – 27 = a = 69 Ronald Reagan was 69 years old when he became president.

2-6 Subtraction Equations y – 23 = 3923 is subtracted from y y = 62 Add 23 to both sides to undo the subtraction. Check y – 23 = 39 Substitute 62 for y in the equation. Solve y – 23 = 39. Check your answer. 62 is the solution. 39 = 39 ? Additional Example 1A: Solving Subtraction Equations 62 – 23 = 39 ? + 23

2-6 Subtraction Equations 78 = s – 1515 is subtracted from s = s Add 15 to both sides to undo the subtraction. Check 78 = s – 15 Substitute 93 for s in the equation. Solve 78 = s – 15. Check your answer. 93 is the solution. 78 = 78 ? Additional Example 1B: Solving Subtraction Equations 78 = 93 – 15 ? + 15

2-6 Subtraction Equations z – 3 = 12 3 is subtracted from z. + 3 z = 15 Add 3 to both sides to undo the subtraction. Check z – 3 = 12 Substitute 15 for z in the equation. Solve z – 3 = 12. Check your answer. 15 is the solution. 12 = 12 ? Additional Example 1C: Solving Subtraction Equations 15 – 3 = 12 ? + 3

2-6 Subtraction Equations a – 4 = 7 4 is subtracted from a. + 4 a = 11 Add 4 to both sides to undo the subtraction. Check a – 4 = 7 Substitute 11 for a in the equation. Solve a – 4 = 7. Check your answer. 11 is the solution. 7 = 7 ? 11 – 4 = 7 ? + 4 Check It Out: Example 1A

2-6 Subtraction Equations 57 = c – 1313 is subtracted from c = c Add 13 to both sides to undo the subtraction. Check 57 = c – 13 Substitute 70 for c in the equation. Solve 57 = c – 13. Check your answer. 70 is the solution. 57 = 57 ? 57 = 70 – 13 ? + 13 Check It Out: Example 1B

2-6 Subtraction Equations g – 62 = 1462 is subtracted from g g = 76 Add 62 to both sides to undo the subtraction. Check g – 62 = 14 Substitute 76 for g in the equation. Solve g – 62 = 14. Check your answer. 76 is the solution. 14 = 14 ? 76 – 62 = 14 ? + 62 Check It Out: Example 1C

2-6 Subtraction Equations Standard Lesson Quiz Lesson Quizzes Lesson Quiz for Student Response Systems

2-6 Subtraction Equations 1. x – 9 = = x – 3 3. x – 7 = = x – x – 9 = 11 Lesson Quiz 6. Susan is taller than James. The difference in their height is 4 inches. James is 62 inches tall. How tall is Susan? x = 30 x = 17 x = 18 x = 30 x = inches

2-6 Subtraction Equations Lesson Quiz for Student Response Systems 1. Solve the equation x – 17 = 36. A. x = 19 B. x = 21 C. x = 36 D. x = 53

2-6 Subtraction Equations Lesson Quiz for Student Response Systems 2. Solve the equation 20 = x – 6. A. x = 14 B. x = 20 C. x = 26 D. x = 40

2-6 Subtraction Equations Lesson Quiz for Student Response Systems 3. Solve the equation y – 16 = 33. A. y = 59 B. y = 49 C. y = 23 D. y = 17

2-6 Subtraction Equations Lesson Quiz for Student Response Systems 4. Solve the equation 52 = y – 23. A. y = 29 B. y = 31 C. y = 75 D. y = 84

2-6 Subtraction Equations Lesson Quiz for Student Response Systems 5. Solve the equation x – 15 = 22. A. x = 43 B. x = 37 C. x = 13 D. x = 7

2-6 Subtraction Equations Lesson Quiz for Student Response Systems 6. During an NBA playoff game, Brand scored 12 points more than Cassell. If Cassell had 33 points how many points did Brand score? A. 45 points B. 33 points C. 21 points D. 12 points