Glencoe Math: Course 3, Volume 2
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Glencoe Math: Course 3, Volume 2 View details
5. Surface Area of Cones
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Exercise 16 Page 637

The lateral area of a right cone is half the product of the circumference of the base and the slant height.

360.7m^2

Practice makes perfect

We want to find the lateral area of the given cone.

To do so, we must know that the lateral area of a right cone is half the product of the circumference of the base and the slant height. L.A.=1/2* 2π r* l ⇔ L.A.=π rl In this formula, r is the radius and l is the slant height of the cone. Since we know that the diameter d is equal to 16.4, we can divide it by 2 and get the radius of the base. r=16.4/2 ⇒ r= 8.2 With this information we are able to calculate the lateral area of the cone. To do so, we will substitute r= 8.2 and l= 14 into the formula for the lateral area. Let's do it!
L.A.=π rl
L.A.=π ( 8.2)( 14)
L.A.=π (114.8)
L.A.=114.8π
L.A.=360.654836...
L.A.≈ 360.7
The lateral area of the given cone, to the nearest tenth, is 360.7 square meters.