So the problem has no symbols, but we're going to multiply because the fraction on the left is right next to the parentheses.
-5/2 * 1/10x = -5x/20
I put "x" next to the 5 because the "x" counts as part of the numerator. Now that it's 5x over 20 that equals one, I'd first reduce -5x/20 into -x/4, then do
-x/4 * -4 = 1 * -4
To make the "x" side equal one, we have to multiply both sides by -4, to make both sides equal.
