SOLUTION: a polygon has 90 diagonals. how many sides does it have?

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Question 222148: a polygon has 90 diagonals. how many sides does it have?
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


There are



diagonals in a -sided polygon. Set the formula equal to 90 and solve for .

Hint: You will end up with a factorable quadratic. You will get two roots. Exclude the negative root because you cannot have a negative number of sides.


John