S = -15
-12s -11 = -11s + 4
Add 11s to both sides and cancel out the 11’s on the right side to get the variable on one side.
-s -11 = 4
Add -11 to both sides and cancel to get the number on the left side.
-s =15
But, s the variable cannot be negative so divide -1 from each side to get rid of the negative.
s = -15