Question 1138783
g^-1(-7) = 4 (note that inverse functions swap the x and y coordinates and the
coordinate (4,-7) is swapped to (-7,4)

h^(-1)x=....
let y = 3x-13
swapping the x and y,
x = 3y-13
making y the subject of the equation,
y = (x+13/3)
and hence h^(-1)x=(x+13/3)

h(x) = 3x-13
h(h(x)) = 3(3x-13) - 13
h(h(x)) = 9x - 39 - 13
h(h(x)) = 9x - 52
when x = 8,
9(8) - 52 = 72 - 52 = 20