HW: page 64 #8-17 ANSWERS

6th Grade Math: HW Ch. 2-5 Page 67 #7-15 all

Learn to solve whole-number subtraction equations. 2-5 Solving Subtraction Equations Course 1 Today’s Learning Goal Assignment Learn to solve whole-number subtraction equations.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Warm Up Problem of the Day Lesson Presentation Course 1 Course 1

Solving Subtraction Equations 2-5 Solving Subtraction Equations Warm Up Simplify. 1. x + 7 = 22 2. 18 + x = 105 3. 16 = x + 9 4. 23 = x + 4 x = 15 x = 87 x = 7 x = 19 Course 1

Solving Subtraction Equations Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 Solving Subtraction Equations Problem of the Day Bruce has 25 CD’s remaining after giving 14 to John, 17 to Mary, and 25 to Sue. How many CD’s did he begin with? 81

Learn to solve whole-number subtraction equations. 2-5 Solving Subtraction Equations Course 1 Today’s Learning Goal Assignment Learn to solve whole-number subtraction equations.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 When John F. Kennedy became president of the United States, he was 43 years old, which was 8 years younger than Abraham Lincoln was when Lincoln became President. How old was Lincoln when he became president?

= = – – 2-5 Solving Subtraction Equations a – 8 = 43 + 8 + 8 a = 51 Course 1 Let a represent Abraham Lincoln’s age. Abraham Lincoln’s age 8 John F. Kennedy’s age – = – = a 8 43 a – 8 = 43 + 8 + 8 a = 51 Abraham Lincoln was 51 years old when he became president.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 Additional Example 1A: Solving Subtraction Equations Solve y – 23 = 39. Check your answer. y – 23 = 39 23 is subtracted from y. + 23 + 23 Add 23 to both sides to undo the subtraction. y = 62 Check y – 23 = 39 62 – 23 = 39 ? Substitute 62 for y in the equation. 39 = 39 ?  62 is the solution.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 Additional Example 1B: Solving Subtraction Equations Solve 78 = s – 15. Check your answer. 78 = s – 15 15 is subtracted from s. + 15 + 15 Add 15 to both sides to undo the subtraction. 93 = s Check 78 = s – 15 78 = 93 – 15 ? Substitute 93 for s in the equation. 78 = 78 ?  93 is the solution.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 Additional Example 1C: Solving Subtraction Equations Solve z – 3 = 12. Check your answer. z – 3 = 12 3 is subtracted from z. + 3 + 3 Add 3 to both sides to undo the subtraction. z = 15 Check z – 3 = 12 15 – 3 = 12 ? Substitute 15 for z in the equation. 12 = 12 ?  15 is the solution.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 Try This: Example 1A Solve a – 4 = 7. Check your answer. a – 4 = 7 4 is subtracted from a. + 4 + 4 Add 4 to both sides to undo the subtraction. a = 11 Check a – 4 = 7 11 – 4 = 7 ? Substitute 11 for a in the equation. 7 = 7 ?  11 is the solution.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 Try This: Example 1B Solve 57 = c – 13. Check your answer. 57 = c – 13 13 is subtracted from c. + 13 + 13 Add 13 to both sides to undo the subtraction. 70 = c Check 57 = c – 13 57 = 70 – 13 ? Substitute 70 for c in the equation. 57 = 57 ?  70 is the solution.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 Try This: Example 1C Solve g – 62 = 14. Check your answer. g – 62 = 14 62 is subtracted from g. + 62 + 62 Add 62 to both sides to undo the subtraction. g = 76 Check g – 62 = 14 76 – 62 = 14 ? Substitute 76 for g in the equation. 14 = 14 ?  76 is the solution.

Solving Subtraction Equations 2-5 Solving Subtraction Equations Course 1 Lesson Quiz 1. x – 9 = 21 2. 14 = x – 3 3. x – 7 = 11 4. 16 = x – 14 5. x – 9 = 11 x = 30 x = 17 x = 18 x = 30 x = 20 6. Susan is taller than James. The difference in their height is 4 inches. James is 62 inches tall. How tall is Susan? 66 inches