It is 168.
This happens because
9 x 12 = 108.
Then you would have to multiply 4 by 15 and get 60.
Next you add 108 with 60, and get 168.
Remember,after multiplying nine by twelve and get 108, you have to divide by two. Then since there are two sides in the triangle you multiply by two and get 108.
In other words your answer is 168
Hope I helped!
:)