Adding integers review web
- 2. Bell Ringer • A positive + a positive is (always, sometimes, never) a positive. • A positive + a positive is (always, sometimes, never) a negative. • A negative + a negative is (always, sometimes, never) negative. • A positive + a negative is (always, sometimes, never) a positive.
- 3. Bell Ringer • A positive + a positive is (always, sometimes, never) a positive. o POSITIVE • A positive + a positive is (always, sometimes, never) a negative. o NEVER • A negative + a negative is (always, sometimes, never) negative. o ALWAYS • A positive + a negative is (always, sometimes, never) a positive. o SOMETIMES
- 4. Where we were… • Adding integers o Same signs… o Opposite signs… • Subtracting Integers o Additive inverse • Absolute value
- 5. Where we are… • Students will learn to… o Review the rules for adding integers.
- 6. Homework
- 7. Unit Plan • I can… represent addition and subtraction on a horizontal number or vertical number line. o Rate yourself and date • I can… solve real-world and mathematical problems involving the four operations with rational numbers. o Rate yourself and date
- 8. Where we are going… • Quiz on Friday o Adding integers o Subtracting integers
- 9. Adding Integers • Power Write #1 o Describe the rules for adding integers with the same signs… • Power Write #2 o Describe the rules for adding integers with opposite signs…
- 10. Adding Integers • Power Write #1 o Describe the rules for adding integers with the same signs… • Add the numbers, keep the common sign • Power Write #2 o Describe the rules for adding integers with opposite signs… • Subtract the numbers, keep the sign of the number with the larges absolute value.
- 11. -10 + (-20) • How do you know?
- 12. -10 + (-20) • How do you know? • - 30; add and keep the common sign
- 13. -20 + (-10) • What property allows you to switch the order of addition?
- 14. -20 + (-10) • What property allows you to switch the order of addition? • - 30; commutative property
- 15. - ½ + (- ½ )
- 16. - ½ + (- ½ ) • - 1
- 17. 15 + (-9)
- 18. 15 + (-9) • 6
- 19. -13 + 20
- 20. -13 + 20 • 7
- 21. -7 + ___ = 0 • What is this called?
- 22. -7 + ___ = 0 • What is this called? • 7; zero pairs, additive inverse, opposites
- 23. -9 + 9 + (-14)
- 24. -9 + 9 + (-14) • -14
- 25. Algebra • The sum of a number and -20 = 40. What is the number?
- 26. Algebra • The sum of a number and -20 = 40. What is the number? • 60 + (-20) = 40
- 27. x + y When: x = 5, y = -1
- 28. x + y When: x = 5, y = -1 5 + (-1) = 4
- 29. Word Problem • A football team gained 7 yards on the first play, lost 9 yards on the second play and gained 6 yards on the third play. To get a first down, they must gain 10 yards on 4 plays. • Write an addition expression that shows this scenario. • How many yards will the team need to gain on it’s fourth play to get a first down?
- 30. Word Problem • A football team gained 7 yards on the first play, lost 9 yards on the second play and gained 6 yards on the third play. To get a first down, they must gain 10 yards on 4 plays. • Write an addition expression that shows this scenario. o 7 + (-9) + 6 • How many yards will the team need to gain on it’s fourth play to get a first down? o They have gained 4 yards, so they need 6 more yards for a first down.
- 31. Homework • Adding integers review worksheet • Due tomorrow.