Question

The points (2,-20) and (r,-5) lie on a line with slope 5/4. Find the missing coordinate r.

Answer 1

I took a picture because it may be a little difficult to understand if I wrote it in text. Hope this helps.

Answer 2

Answer: 14

Explanation:

The formula for slope in this problem is:

`(-5-(-20))/(r-2)=(5)/(4)`

`(15)/(r-2) = (5)/(4)` (cross multiply)

60 = 5(r-2)

60 = 5r - 10

70 = 5r

14 = r

Check: (2, -20) (14, -5)

`(-5-(-20))/(14-2)`

`(15)/(12)`

`(5)/(4)`