Algebra 1 Notes: Lesson 2-2 Rational Numbers

1. Algebra 1 Notes:Lesson 2-2Rational Numbers

2. Visualize or Draw a Number line to help + means right - means left

3. Example 1 • Add: • 6 + (-14)

4. Example 1 • Add: • 6 + (-14) = -8 • -¾ + (-½)

5. Example 1 • Add: • 6 + (-14) = -8 • -¾ + (-½) = -1¼

6. Subtraction of Rational Numbers To subtract a rational number, add its additive inverse. 8 – 15 = 8 + (-15) -7.6 – 12.3 = -7.6 + (-12.3)

7. Example 2 • Rewrite as an addition problem, then add: • -19 – 8

8. Example 2 • Rewrite as an addition problem, then add: • -19 – 8 = -19 + (-8)

9. Example 2 • Rewrite as an addition problem, then add: • -19 – 8 = -19 + (-8) = -27 • 67.1 – (-38.2)

10. Example 2 • Rewrite as an addition problem, then add: • -19 – 8 = -19 + (-8) = -27 • 67.1 – (-38.2) = 67.1 + 38.2

11. Example 2 • Rewrite as an addition problem, then add: • -19 – 8 = -19 + (-8) = -27 • 67.1 – (-38.2) = 67.1 + 38.2 = 105.3

12. Multiplication and Division of Integers Same Signs Multiply or divide as usual; the solution is positive. Different Signs Multiply or divide as usual; the solution is negative.

13. Example 3 • Multiply or Divide: • (-8)(-6)

14. Example 3 • Multiply or Divide: • (-8)(-6) = 48 • -108 18

15. Example 3 • Multiply or Divide: • (-8)(-6) = 48 • -108 =-6 18

16. Example 4 Simplify:

17. Example 5 Simplify:

18. Assignment Worksheet: Rational Numbers