1. Warm ups Find the slope: 1. (2,1) (8,9) 2. (7,-8) (14,-6) 3. (-4,-1) (-2,-5) 4. (4,1) (-4,1) 5. (3,2) (3,-2) Answers: 1.4/3 2.2/7 3.-2 4.Zero 5.No slope

2. 6-1 Slope Objective: To find a missing coordinate given two points and the slope.

3. Example 1 Find the missing coordinate (r) (-1,-3) (7, r) m = ¾ 3 = r – (-3) 4 7 – (-1) 3 = r + 3 4 8 4(r + 3) = 3(8) 4r + 12 = 24 4r = 12 r = 3 m = y 2 – y 1 x 2 – x 1 **This is a proportion Cross multiply! x 1 y 1 x 2 y 2

4. Example 2 Find the missing coordinate (r) (-4,-1) (r, -5) m = -2 -2 = -5 – (-1) 1 r – (-4) -2 = -4 1 r + 4 -2(r + 4) = 1(-4) -2r – 8 = -4 -2r = 4 r = -2 m = y 2 – y 1 x 2 – x 1 **This is a proportion Cross multiply! x 1 y 1 x 2 y 2

5. TOO Find the missing coordinate (r) (-2,r) (10,4) m = -1/2 -1 = 4 – r 2 10 – (-2) -1 = 4 - r 2 12 2(4 – r) = -1(12) 8 – 2r = -12 -2r = -20 r = 10 m = y 2 – y 1 x 2 – x 1 **This is a proportion Cross multiply! x 1 y 1 x 2 y 2

6. Example 3 Find the missing coordinate (r) (12,r) (r,6) m = 2 2 = 6 – r 1 r – 12 1(6 – r) = 2(r – 12) 6 – r = 2r – 24 6 = 3r – 24 30 = 3r r = 10 m = y 2 – y 1 x 2 – x 1 **This is a proportion Cross multiply! x 1 y 1 x 2 y 2 Combine like terms

7. Homework Pg. 330 #30-38 Show all of your work

8. ZONK Let’s the games begin!!