Function a(b) relates the area of a trapazoid with a given hight of 12 and one base length of 9 with the length of its other base it takes as input the other base value and returns as output the area of the trapazoid a(b)=12*b+9/2 which equation below represents the inverse function b(a) which takes the trapazoids area as input and returns as output the length of the other base