Surface Area of Cubes, Rectangular
Prisms, and Cylinders
13-14
The surface area of a solid figure is the sum of the areas of all its faces.
To find the surface area of a polyhedron, look at its net.
Find the surface area of a cube that
measures 2
1
2 ft on an edge.To find the surface area of a cube:Find the area of one square face.Multiply the area by 6 since all six
faces of a cube are congruent.The surface area of the cube is 37
1
2 ft(^2).
Find the surface area of a rectangular prism that
measures 10 cm long, 3 cm wide, and 5 cm high.
To find the surface area of a rectangular prism:
Surface Area of a Cube
S 6 e^2
Surface Area of a Rectangular Prism
S 2 w 2 wh 2 h
A^52 ft^52 ft^245 ft^2
3
S^61 ^245 ft^2 37 ^12 ft^2
2
Find the area of one of each
parallel faces and then double
the area.
Find the sum of the areas.
Area of top and bottom faces 2(10 cm 3 cm) 60 cm^2
Area of side faces 2( 3 cm 5 cm) 30 cm^2
Area of front and back faces 2(10 cm 5 cm) 100 cm^2
Surface Area (S) 190 cm^2
The surface area of the rectangular prism is 190 cm^2.
2 ft^12
e 2 ft^12 ^52 ft
2 ft^12
e
e
10 cm
w 3 cm
h 5 cm
w
h front
side bottom side
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