SOLUTION: A regular polygon has 6 times as many diagonals as sides. How many sides does this polygon have? How do you solve it,whats the strategy?

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Question 943814: A regular polygon has 6 times as many diagonals as sides. How many sides does this polygon
have? How do you solve it,whats the strategy?
Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

A regular polygon has 6 times as many diagonals as sides. How many sides does this polygon
have? How do you solve it,whats the strategy?
No special strategy!! Just the use of the formula.

Formula for determining the number of diagonals of a polygon: n%28n+-+3%29%2F2, with n being the number of sides

Since there are 6 times as many diagonals as numbers of sides, then number of diagonals = 6n

We now have: n%28n+-+3%29%2F2+=+6n

%28n%5E2+-+3n%29%2F2+=+6n

n%5E2+-+3n+=+12n ------ Cross-multiplying

n%5E2+-+3n+-+12n+=+0

n%5E2+-+15n+=+0

n(n - 15) = 0

Number of sides, or highlight_green%28n+=+15%29       OR       n = 0 (ignore)