Answer:
(3h+18) = (15h)
3h +18 = 15h
subtracting 3h from both sides
=> 3h + 18 - 3h = 15h - 3h
=> 18 = 12h
Dividing by 12 both sides
=> 18/12 = 12h/12
=> 3/2 = h
=> 1.5 = h
=> h = 1.5
h = 1.5
h = 1.5 if (3h+18) = (15h)
or
3h + 18 + 15h = 180
=> 18h + 18 = 180
Dividing by 18 both sides
=> h + 1 = 10
=> h = 9