Pearson Geometry Common Core, 2011
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Pearson Geometry Common Core, 2011 View details
Chapter Review
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Exercise 11 Page 752

Use the formula for the surface area of a prism.

36 cm^2

Practice makes perfect

The given solid is a prism.

To calculate the surface area of a prism, we can use the known formula where P is the perimeter of the base, h is the height, and B is the area of the base. S=Ph+2B We can see that the base is a right triangle. We are given the lengths of both legs, but not the length of the hypotenuse. Let's use the Pythagorean Theorem to find the length of the hypotenuse. hypothenuse = sqrt(3^2 + 4^2) ⇔ hypothenuse = 5 Let's add the lengths of the three sides of the triangle to find the perimeter. P=3+4+5=12cm We can calculate the area of the base using the formula for the area of a triangle.
B=1/2bh
B=1/2( 4)( 3)
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Simplify right-hand side
B=1/2(12)
B=12/2
B=6
The area of the base is 6cm^2. Now we have enough information to find the surface area of the prism. Let's substitute P with 12, h with 2, and B with 6 into the formula.
S=Ph+2B
S=( 12)( 2)+2( 6)
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Simplify right-hand side
S=24+12
S=36
The surface area of the prism is 36cm^2.