Answer: The answer is 90.
Step-by-step explanation: This is because if you cut the shape horozontaly than it is going to be seperated and the equation will looks like this:
(6 x 9) + (6 x 6)
6 x 9 is 54 and 6 x 6 is 36
If you add them together than you get 90.
Sorry if it is wrong but hope it helps you in any way!