SOLUTION: The sum of the interior angle measures of a convex polygon is 1980 degrees . How many sides does it have?

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Question 405814: The sum of the interior angle measures of a convex polygon is 1980 degrees . How many sides does it have?
Found 2 solutions by Alan3354, MathLover1:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Sum = 180*(n-2) = 1980
n-2 = 11
n = 13

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

If a convex polygon has n sides, then its interior+angle+sum is given by the following equation: S+=+%28+n+-2%29+%D7+180°.

S+=+%28+n+-+2%29+%D7+180......plug in your sum and solve for n
1980=+%28+n+-2%29+%D7+180
1980%2F+180+=++n+-2+
11+=+n+-2+
11%2B2+=+n++
13+=+n++