I would use what times 6 = 36 because 6*6+36
Answer: 
Step-by-step explanation:
Given : Two opposite sides of a rectangle are each of length x.
Let the other adjacent side be y.
The perimeter of the rectangle is 12 units.
Perimeter of rectangle is given by :-

The area of rectangle is given by :-

Hence, the area as a function x = 
54c^3d^4 + 9c^4d^2
9c^3d^2(6d^2 + c)