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a semi circle sits on top of a rectangle. find its area and perimeter . use 3.14 for pi sides 3in by 4 in

User Avnera
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1 Answer

5 votes

Answer:

Area=14.28 Perimeter= 14.28

Explanation:

Area of a circle = (3.14) * r^2

radius = diameter/2

radius = 4/2

r = 2

A = (3.14) * 2^2

A = (3.14) * 4

A = 12.57

since it's a half circle though, 12.57/2 = 6.29

the area of the rectangle is bh, 4*2 = 8

6.29 + 8 = 14.28

area = 14.28

perimeter of a circle, or circumference = 2(3.14)r

C = 2(3.14) * 2

C = 6.28 * 2

C = 12.57

but again, since it's a half circle, 12.57/2 = 6.29

perimeter of a rectangle = 2(l + w)

p = 2(4 + 2)

p = 2(6)

p = 12

but because the perimeter is what's on the outside, we don't count the side connecting to the circle, so it'd be 12 - 4 = 8

6.29 + 8 = 14.28

perimeter = 14.28

User Alexandre Santos
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