Answer:
x=2
Step-by-step explanation:
2x+8=8x-4
2x+12=8x
12=6x
2=x
x=2
I think the answer would be D
Check the picture below.
so, to get the area of the triangles, we can simply run a perpendicular line from the top to the base, and end up with a right-triangle with a base of 22 and a hypotenuse of 34, let's find the altitude.

so then the surface area of the triangular prism is,
5/8 as a percentage is 62.5
hope i helped :D