To find the surface area you will need to find the area of all 5 surfaces (faces) on the prism. On a triangular prism there are 2 triangular faces and 3 rectangular faces. All 3 rectangular faces are the same and the 2 triangular faces are also the same.
To find the area of the triangular faces, you will use the formula for finding the area of a triangle:
A = 1/2bh
1/2 x 10 x 8.7
A = 43.5 in^2
To find the area of the rectangular faces, you will use the formula for finding the area of a rectangle:
A = bh
10 x 3
A = 30 in ^2
30 + 30 + 30 + 43.5 + 43.5 = 177
The minimum amount of wrapping paper needed for the gift is 177 square inches.
Hey!
Hope this helps...
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The first thing we know is that all the answers equal 99, so we cannot cross any answer off, however, what we want to know is what answer (after distribution) looks like 36 + 63...
A.) 11(3 + 6) > 33 + 66
Does 33+66 look like 36+63?
NO
B.) 9(4 + 7) > 36 + 63
Does 36+63 look like 36+63?
YES
C.) 11(4 + 5) > 44 + 55
Does 44+55 look like 36+63?
NO
D.) 3(15 + 18) > 45 + 54
Does 45+54 look like 36+63?
NO
So...
The answer is: B.) 9(4 + 7)
