1. WARM UP 1)Evaluate the expression: a) l5lb) l-13lc) – l0.56l 2)Use mental math to solve the equation: a) lxl = -10b) lxl = 2.7 3)Find the sum: a) -6 + (-7)b) 4 + (-10) 4

2. WARM UP 1)Evaluate the expression: a) l5lb) l-13lc) – l0.56l 2)Use mental math to solve the equation: a) lxl = -10b) lxl = 2.7 3)Find the sum: a) -6 + (-7)b) 4 + (-10) 3

3. WARM UP 1)Evaluate the expression: a) l5lb) l-13lc) – l0.56l 2)Use mental math to solve the equation: a) lxl = -10b) lxl = 2.7 3)Find the sum: a) -6 + (-7)b) 4 + (-10) 2

4. WARM UP 1)Evaluate the expression: a) l5lb) l-13lc) – l0.56l 2)Use mental math to solve the equation: a) lxl = -10b) lxl = 2.7 3)Find the sum: a) -6 + (-7)b) 4 + (-10) 1

5. 1)Evaluate the expression: a) l5lb) l-13lc) – l0.56l 2)Use mental math to solve the equation: a) lxl = -10b) lxl = 2.7 3)Find the sum: a) -6 + (-7)b) 4 + (-10) WARM UP 0

6. 9/25/2012 2.4 Subtracting Real Numbers GOALSubtract real numbers using the subtraction rule KEY WORDS: Term

7. Subtracting Real #s Some addition expressions can be evaluated using subtraction ADDTION PROBLEM SUBTRACTION PROBLEM 5 + (-3) = 25 – 3 = 2 -2 + (-6) = -8-2 – 6 = -8

8. Subtracting Real #s To subtract b from a, add the opposite of b to a. a – b = a + (-b) EXAMPLE: 3 – 5 = 3 + (-5)

9. Subtracting Real #s EXAMPLES a. 10 – 11b. 11 – 10 10 – 11 = 10 + (-11) = -1 11 – 10 = 11 + (-10) = 1

10. Subtracting Real #s Expressions with more than one subtraction EX: 4 – (-4) - 5 4 – (-4) – 5 =4 + 4 + (-5) 8 + (-5) 3

11. PRACTICE a.4 – 5 b. 0 – (-7) c. -2 - 8

12. PRACTICE d. 2 – (-3) – 6 e. -3 -2 – (-5)