How do you prove that the interior angles of a pentagram equal 180

Question

unklerhaukus · Answer

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sum of interior angles of a pentagon are equal to 540° ,

unklerhaukus · Answer

each triangle has an angle sum of 180°

unklerhaukus · Answer

ops the question is about pentaGRAMS

unklerhaukus · Answer

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unklerhaukus · Answer

which angles are the interior angle in the pentagram

anonymous · Answer

Not pentagon, pentagram. five pointed star
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unklerhaukus · Answer

well in the case of a regular pentagram, (equal angles and lengths) the angle at each point is 36°, 
5 times 36 is 180

anonymous · Answer

In the pentagon all the angles add up to 540. the pentagram angles is a subset of that. The pentagram angles add up to 180. but how do I prove that in a way so that I can figure the sume of interior angles of any irregular poly GRAM.

anonymous · Answer

Yeah the regular one is easy to prove

unklerhaukus · Answer

you might have to do some cnstruction

unklerhaukus · Answer

construction *

anonymous · Answer

clearly. any ideas what kind of construction might be useful here.

unklerhaukus · Answer

i would try some thing like this 
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i dont know if it will be easy though