Question 1128436
The area, A = b*h/2
b = A - 4
h = A - 9
Substitute in the formula for the area
A = (A-4)(A-9)/2
2A = A^2 - 13A + 36
A^2 - 15A + 36 = 0
This can be factored as
(A-3)(A-12) = 0
This gives A = 3, A = 12
We take the larger of the two solutions since A=3 would mean that the base and height are negative
Ans: 12 units