Pearson Geometry Common Core, 2011
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Pearson Geometry Common Core, 2011 View details
4. Volumes of Prisms and Cylinders
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Exercise 11 Page 721

Use the formulas for the area of a triangle and volume of a prism.

22.5ft^3

Practice makes perfect

We are given the following triangular prism, and we want to find its volume.

The volume of a prism can be calculated using the following formula. V=Bh Where B is the area of the base and h is the height of the prism. Note that the base of the prism is a right triangle, so we can calculate its area using the formula for area of a triangle.

B=1/2bh
B=1/2( 3)( 3)
â–¼
Evaluate right-hand side
B=1/2(9)
B=9/2

The area of the base B is 92ft^2, and we are given that the height equals 5ft. Let's substitute these values into the formula and solve for V.

V=Bh
V=( 9/2)( 5)
V=45/2
V=22.5

Therefore, the volume of the prism is 22.5ft^3.