Answer:
SA=736ft²
Step-by-step explanation:
First I like to start with the triangles
[tex]a =2 \frac{1}{2} bh \\ [/tex]
The reason why we would multiply the triangle area by two is because where finding the area of the triangle in the Back and in the front
[tex]a = 2 \frac{1}{2} (12 \times 8) = 96[/tex]
then we go to the rectangles of the left and right
[tex]a = 2bh[/tex]
[tex]a = 2(20 \times 10) = 400[/tex]
again because the numbers for the base and height of the two rectangles are the same we are going to times by two.
Then we going to find the area for the base of the triangular prism, which would be the bottom rectangle
[tex]a = bh[/tex]
there are no same shapes with the same base and height so where not going to multiply by two
[tex]a = 12 \times 20 = 240[/tex]
now we add all the area that we found up
[tex]400 + 96 + 240 = 736[/tex]
now we have 736ft and since where finding SA we square it
SA=736ft²