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I need help with this

I need help with this-example-1

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Answer:

  • perimeter: 20 units
  • area: 27.5 square units

Explanation:

We must assume the pentagon is regular. Its 5 sides are all the same length as AB, which is 4 units. So, the perimeter is ...

P = 5s = 5(4) = 20 . . . units

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The area is given by the formula ...

A = (1/2)Pa

where P is the perimeter and a is the apothem--the distance from the center to one side.

The center coordinates are (3, 4.75), so the center is 2.75 units from side AB at y=2. Then the area is ...

A = (1/2)(20)(2.75) = 27.5 . . . square units

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