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2 years ago

Identify the surface area of the composite figure in terms of π.

Mathematics

1 answer:

Katena32 [7]2 years ago

7 0

Answer:

78π m²

Step-by-step explanation:

The lateral area of the cylinder is ...

LA = 2πrh

LA = 2π(3 m)(8 m) = 48π m²

The lateral area of one cone is ...

LA = πrh . . . . where h is the slant height

LA = π(3 m)(5 m) = 15π m²

Then the total surface area of the figure is the area of the two cones plus that of the cylinder:

S = 2(cone area) + cylinder area

S = 2(15π m²) +(48π m²)

S = 78π m²

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