Answer:
204 in
Explanation:
I can't really explain this other than that you have to add all the sides and the outside of this shape. For the hypotenuse you use the formula
. Now just fill in what you know.

So we have:
length: 12in
base: 9in
hypotenuse: 15in
So now we do 12+15+9+15+12+15+9+15+12+15+9+15+12+15+9+15. Once we do all that we get 204 in.