Answer:
You need 443.2 square inches of wrapping paper to completely cover the prism.
Explanation:
Calculate the area of each side.
Triangles:
Base * Height * 1/2
10 in. * 8.7 in. * 1/2
87 in.^2 * 1/2
43.5 in.^2
There are two sides with the triangle so we multiply the 43.5 in.^2 by two
(43.5 in.^2) * 2
87 in.^2
Side Rectangles:
Length * Width
13 in. * 8.7 in.
113.1 in.^2
There are two sides with this size rectangle so we multiply the 113.1 in.^2 by two
(113.1 in.^2) * 2
226.2 in.^2
Bottom Rectangle
Length * Width
13 in. * 10 in.
130 in.^2
There is only one side with the bottom rectangle.
Add up all the calculate areas.
Triangles + Side Rectangles + Bottom Rectangle
87 in.^2 + 226.2 in.^2 + 130 in.^2
443.2 in.^2