Isolate the x. Note the equal sign. What you do to one side, you do to the other.
First, subtract 2 from both sides
2 (-2) - x = (5/8) - 2
-x = 5/8 - 2
Make sure they have the same denominator. Remember that what you multiply to the denominator, you multiply the numerator:
-x = 5/8 - 16/8
-x = - 11/8
Isolate the x. Divide -1 from both sides
(-x)/-1 = (-11/8)/-1
x = 11/8
11/8 is your answer for x
~Rise Above the Ordinary