Big Ideas Math: Modeling Real Life, Grade 7
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Big Ideas Math: Modeling Real Life, Grade 7 View details
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Exercise 4 Page 450

To find the lateral surface area of a cylinder use the formula S = 2π rh. Then, use the formula for the surface area of a cylinder.

Lateral Surface Area: 37.7cm^2
Surfacea Area: 62.83cm^2

We want to find the surface area and the lateral surface area of the given cylinder.

cylinder

The surface area of a cylinder is a sum of its lateral surface area and the areas of the two bases.

Lateral Surface Area

To calculate the lateral surface area of a cylinder, we can use the following formula. L=2π rh In this formula, r is the radius of the base and h is the height of the cylinder. In our case, the base's radius is 2 centimeters and the height is 3 centimeters. By substituting 2 for r with 3 for h in the above formula, we can solve for S. Let's do it!
L=2π rh
L=2π( 2)( 3)
L=12π
L=37.699111...
L ≈ 37.7
We found that the lateral surface area of the cylinder is about 37.7 square centimeters. Now, let's find the surface area of the cylinder.

Surface Area

The surface area of a cylinder is a sum of the lateral surface area and the areas of the two circular bases. We can find it using the following formula. S = L + 2 π r^2 Here, L is the lateral surface area and r is the radius of the base. In our case, L ≈ 37.7 square centimeters and r = 2 centimeters. Let's substitute these values into our formula and find the surface area!
S = L + 2 π r^2
S = 37.7 + 2 π ( 2)^2
Simplify right-hand side
S = 37.7 + 2 π (4)
S = 37.7+ 8 π
S = 62.832741...
S ≈ 62.83
The surface area of our cylinder is about 62.83 square centimeters.