SOLUTION: The sum of the interior angles of a polygon is 9x^2. If x is 3 greater than the number of sides of the polygon, how many sides does the polygon have?
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Question 1143505: The sum of the interior angles of a polygon is 9x^2. If x is 3 greater than the number of sides of the polygon, how many sides does the polygon have? Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! The sum of the interior angles of a polygon is 9x^2. If x is 3 greater than the number of sides of the polygon, how many sides does the polygon have?
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n sides.
Sum of angles = 180*(n-2) = 9x^2
x^2 = 20n - 40
x = n+3
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x^2 = 20(x-3) - 40 = 20x -100
x^2 - 20x + 100 = 0
x = 10
# of sides = 7
