A pyramid has a base in the shape of a rhombus and a peak directly above the base's center. The pyramid's height is 7, its base's sides have lengths of 5, and its base has a corner with an angle of 5π8. What is the pyramid's surface area?

1 Answer
Jan 23, 2018

Total Surface Area

TSA=AT=AL+AR=23.097+74.3303=97.4273

Explanation:

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Area of Rhombus base AR=aasinθ

AR=55sin(5π8)23.097

Area of slant triangle At=(12)ahl where a is the rhombus base length and hlis the slant height of the triangle.

hl=h2+(a2)2 where h is the pyramid’s height.

Lateral Surface Area AL=4At=4(12)572+(52)2

LSA=AL=74.3303

Total Surface Area TSA=AT=AL+AR=23.097+74.3303=97.4273