surface area of a net
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Answer:
Step-by-step explanation:
This is really a sloppy diagram. You have to know if the base of the triangle is 5 or 10.
It is 5. So the area of 1 of the triangles is 1/2 * b * h
b = 5
h = 8.7
Area = 1/2 * 8.7 * 5 = 21.75
There are 4 such triangles. The total area = 4 * 21.75 = 87 sqr in