ANSWER: 864
First you do 12 times 12 that is 144 then you divide it by 2 because it is a triangle
Then 12 times 44 and get 500 something and divide it by 2 because it is also a triangle and get 264 then you subtract 56 and 12 and get 44 and times that by 12 and get 528 then you add up all the numbers and should get 864