Answer:
<h2>c. 16.5</h2>
Step-by-step explanation:
It's the right triangle.
The formula of an area of a right triangle:

Look at the picture.
We have

Substitute:

3x + 9 = 90
3x = 90 - 9 = 81
x = 81/3 = 27
x = 27
Answer:
116
Step-by-step explanation:
8.2 / 2 = 4.1
a = 
0.5 x 8.2 x 5.6736 = 23.2618
23.2618 x 5 = 116.309 = 116
753,249 - 575,388 = 159,861
i hope it's right :)