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PLEASE HELPPP 20 pts: interior and exterior polygon sums! (1 and 2) if you can please explain because I don't get it at all

PLEASE HELPPP 20 pts: interior and exterior polygon sums! (1 and 2) if you can please-example-1

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Hi there!

In order to figure out the total measures of interior angles of a polygon, you can use this equation: (n-2) * 180.

#1 - First, let's figure out the total measure of interior angles

WORK:
(6 - 2) * 180 = 720

Next, we can add up all of the values and set it equal to the total interior angle measures. Since the two unknown angles are congruent, we can show those as 2x.

WORK:
90 + 149 + 103 + 108 + 2x = 720
2x + 441 = 720
2x = 279
x = 139.5 degrees

#2 - In any polygon, the value of the exterior angles always adds up to 360. Using that, we can create another equation, adding up the values and setting it equal to 360. For the one interior angle that is there, we need to find it's supplementary angle.

WORK:
43 + (180 - 106) + 11x + 12x + 37 + 17x + 50 + 12x = 360
52x + 204 = 360
52x = 156
x = 3 degrees

Hope this helps!! :)
If there's anything else that I can help you with, please let me know!
User Debanjan Basu
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