How do find surface area of a triangular prism

The triangle Prism has 5 sides.


Area of the bottom rectangle:

Area = 15 x 20 = 300 ft²


Area of the two triangles:

Area = 2 [ 1/2 x 15 x 8] = 120 ft²


Area of the top rectangle:

Area = 20 x 17 = 340 ft²


Area of the side rectangle:

Area = 8 x 20 = 160 ft²


Total Area

300 + 120 + 340 + 160 = 920 ft²


Total Surface area = 920 ft²

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