1. This is a nonagon. A nonagon is a 9-sided polygon; the figure has 9 sides.
2. This is not a regular polygon. A regular polygon is equiangular and equilateral which means that all of the angles are equal in measure and all of the sides are equal in length. The figure shown does not have equal sides or angles; therefore, it is an irregular polygon.
"<em>The distance around a circle"</em> = Circumference
Circumference = 3.14 * diameter
3900 * 3.14 = 12246
The circumference (distance around the crater) is equal to 12,246 feet
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Define the two numbers
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Let the first number be x.
Let the second number be y.
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Form equations and solve x and y
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x + 2y = 14 ------------------ (1)
2x + y = 31 ------------------ (2)
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Equation (1) x 2
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2x + 4y = 28 ---------------(1a)
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Equation (1a) - 2
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3y = 28 - 31
3y = -3
y = -1
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Substitute y = -1 into (1)
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x + 2(-1) = 14
x -2 = 14
x = 14 + 2
x = 16
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Answer: x =16, y = -1
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