Find the perimeter of the following figure?

How would I go about finding the perimeter of the following figure.. I know the formula is pi r squared but I'm so stuck.

http://img.photobucket.com/albums/v631/jay_425/pro...

I tried to recreate it the best I could.

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  • 1 decade ago
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    so the missing piece is 1/2 a circle? in which case:

    find perimeter of the rectangle:

    6m*2 + 8m*2 = 12 + 16 = 28 m

    find circumference of a circle with a diameter of 6m

    -->the formula for circumference is 2*pi*radius OR pi*diameter (- the formula you have in your question is for the area of a circle)

    -->since we know the diameter is 6, use pi*diameter:

    6*3.1415 (or whatever equivalent you were told to use for pi)

    = 18.849

    -->divide by 2:

    18.849/2 = 9.4245 m

    so the perimeter of the figure is the perimeter of the rectangle minus 9.4245 m: (rounded 9.4245 to nearest hundredth: 9.42)

    28 - 9.42 = 18.58 m

    ~~~~~~~~~~~~~~~~~~~~~~~~~

    If you need the area of the figure, find the area of the rectangle and then subtract the area of the half-circle. (area of circle divided by 2).

    Since the diameter was 6, the radius would be 3. (d/2 = r)

    area of rectangle: 6*8 = 48 m^2

    area of circle = pi*r*r = 3.1415*3*3 = 28.2735 divided by 2: 14.14

    area of figure = 48 - 14.14 = 33.86 m^2

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  • 1 decade ago

    Is that a semi-circle (half-circle) a the top?

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