slope: find 'r' so line through (5, r) and (2, -3) has slope

Determine the value of "r" so the line that passes through each pair of points has the given slope.

(5, r), (2, -3), M=4/3

-3-R/2-5=4/3
-3-R/-3

i dont know what to do next.. can u help?...

Rise/Run = (-3-r)/(2-5) = (3+r)/(5-2) = (3+r)/3 = 4/3

You did great! Only four things need improvement.

1) Why did you give up? Don't do that.
2) Why did you change from "r" to "R"? Don't do that. It makes a difference.
3) Fix your notation. -3-r/2-5 is very different from (-3-r)/(2-5). Write clearly.
4) Why did you create that equation? Understanding what you are doing is very helpful. Solve for 'r'. Isn't that what the problem statement demanded?

(3+r)/3 = 4/3

3+r = 4

r = 1

Check.