3/(x-1) - 1/(x^2-1) = 5/(x-1)
Subtract 3/(x-1) from both sides
-1/(x^2-1) = 2/(x-1)
Factor x^2 - 1
-1/[(x-1)(x+1] = 2/(x-1)
Multiply by (x-1)(x+1) on both sides
-1 = 2 (x+1)
-1 = 2x + 2
Subtract 2 from both sides
-3 = 2x
Divide by 2 on both sides
-3/2 = x