SOLUTION: I can not find r my answer seems wrong (2,8)(r,-4) m=-3 please show me step by step

Algebra ->  Linear-equations -> SOLUTION: I can not find r my answer seems wrong (2,8)(r,-4) m=-3 please show me step by step      Log On


   

Question 955849: I can not find r my answer seems wrong
(2,8)(r,-4) m=-3 please show me step by step
Found 2 solutions by Alan3354, MathTherapy:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
What is it you want to do?

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

I can not find r my answer seems wrong
(2,8)(r-4) m=-3 please show me step by step
With a slope, or m of - 3, and points, (2, 8) and (r, -4), we use the slope formula: m+=+%28y%5B1%5D+-+y%5B2%5D%29%2F%28x%5B1%5D+-+x%5B2%5D%29 to get:

-+3+=+%288+-+-+4%29%2F%282+-+r%29

-+3+=+%288+%2B+4%29%2F%282+-+r%29

-+3+=+12%2F%282+-+r%29

-+3%282+-+r%29+=+12 ------ Cross-multiplying

- 6 + 3r = 12

3r = 12 + 6

3r = 18

r+=+18%2F3, or highlight_green%28r+=+6%29