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Answer for number 12

Answer for number 12-example-1
User Dilico
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1 Answer

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Answer:

12 a. 4605 feet 12 b. 1,459,063 square feet

Explanation:

For the perimeter, we simply add the lengths of each of the 5 sides together (or multiply 5 times one side length).

P = 5(921)

P = 4605 feet

For the area, we will use composition...add the area of the triangle to the area of the trapezoid.

For the area of the triangle, the formula is


A=(1)/(2)bh.

Filling in our values gives us


A=(1)/(2)(1490)(541) and

A = 403,045 square feet.

Now for the trapezoid. The formula for a trapezoid is


A=(1)/(2)(b_(1)+b_(2))(h)

where the b's represent the bases and the h represents the height. Filling in our values gives us


A=(1)/(2)(921+1490)(876)

Work inside the parenthesis first:


A=(1)/(2)(2411)(876) and

A = 1,056,018

Now we add those together to get that area of the Pentagon is 1,459,063 square feet

User Ifedi Okonkwo
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