Solve for r:
(r + 3)/(r - 2) = (r - 1)/(r + 1)
Cross multiply:
(r + 1) (r + 3) = (r - 2) (r - 1)
Expand out terms of the left hand side:
r^2 + 4 r + 3 = (r - 2) (r - 1)
Expand out terms of the right hand side:
r^2 + 4 r + 3 = r^2 - 3 r + 2
Subtract r^2 - 3 r + 2 from both sides:
7 r + 1 = 0
Subtract 1 from both sides:
7 r = -1
Divide both sides by 7:
r = -1/7
+1252 (r+3)/(r-2)=(r-1)(r+1)
(r+3)(r+1)=(r-1)(r-2)
r^2+4r+3=r^2-3r+2
7r=-1
r=-1/7
You are very welcome!
:P
