it would be 81, all interior angles should equal 360 and that goes for any closed shape.
Answer:

Step-by-step explanation:
7d – 4d – 3d – 5 = 6d
<em>(7d - 4d = 3d)</em>
3d - 3d -5 = 6d
<em>(3d - 3d = 0)</em>
0 - 5 = 6d
-5 = 6d
-5/6 = 6d/6
d = 
Hope this helps ^-^
Answer:
4.5
Step-by-step explanation:
I think it will work if you Divide 54 over 12 = 4.5
16x11 which equals 176 so that’s the area