You have the following equation:
11h - (2h -1) = 118
In order to solve for h the previous equation you proceed as follow:
11h - (2h -1) = 118
elminate parenthesis by takin into accoun the multilpication of signs
11h - 2h + 1 = 118 simplify similar terms and subtract 1 both sides
9h = 117 divide by 9 both sides
h = 117/9
h = 13
Hence, the solution to the given equation is h = 13