The lateral surface area of a prism is the sum of the areas of that lateral faces. The total surface area the a prism is the amount of the areas of that is lateral faces and also its 2 bases.

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example 1:
discover the lateral surface area that a triangular prism with bases edges 3 inches, 4 inches and 5 inches and altitude 8 inches.

The perimeter is the amount of the bases.
ns = 3 + 4 + 5 = 12 customs
Lateral surface ar Area = 12 ( 8 ) = 96 inch 2
The general formula because that the full surface area that a right prism is T . S . A . = ns h + 2 B wherein ns to represent the perimeter of the base, h the height of the prism and also B the area the the base. there is no easy method to calculation the surface area the an tilt prism in general. The best means is to uncover the areas of the bases and the lateral encounters separately and add them.
instance 2:
discover the total surface area of one isosceles trapezoidal prism through parallel edge of the base 6 cm and also 12 cm, the legs of the basic 5 cm each, the altitude of the base 4 cm and also height of the prism 10 cm.

The perimeter of the base is the amount of the lengths of the sides.
p = 6 + 5 + 12 + 5 = 28 centimeter
because the basic is an isosceles trapezoid, that is area is 1 2 h ( b 1 + b 2 ) .
B = 1 2 ( 4 ) ( 6 + 12 ) = 36 cm 2
T . S .
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A . = ns h + 2 B = 28 ( 10 ) + 2 ( 36 ) = 280 + 72 = 352 cm 2