# Geometry

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In a regular polygon (equal sides and angles), you use (n-2)180 to find out what the interior angle sum is (n=number of sides in polygon) and you divide by that number by whatever n is to find out the measure of an individual angle, right? Well, there is going to be a problem on tomorrow's geometry test where we are given the measure of an interior angle of a regular polygon (for instance, one angle=150 degrees), but I can't tell how to do that. I figured it would be something like this:

(n-2)180
-------- = 150
n

But, it dosn't work out too well when I try to single out n. Can someone tell me how to do this?

P.S. Sorry that my explanation was so long -- I was trying to get the information out there :-) THANKS!!!

• Geometry -

Take an interior angle: 150 degrees. How many sides?

the sum of interior angles is 150n (n angles, each 150 degrees)
but (n-2)180= 150n (both are sum of interior angles, and equal, so
180n-360=150n
30n=360
n= 12

\thats it.

• Geometry -

Oh -- I get it! Thank you so much for helping me out, I really needed that info for tomorrow's test. Thx!

• Geometry -

i have absolutely no idea how to do this!

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