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1 year ago

14

The sum of the measures of the interior angles in a convex polygon is 1,260°. How many sides does the polygon have?

1 answer:

gavmur [86]1 year ago

3 0

The formula for working out the total interior is:

180(n-2) = 1260

So let’s rearrange by dividing both sides by 180 and find what n is:

n-2 = 7

Then let’s add 2 to both sides to find what n is:

n=9

Each interior angle is 1260/9 = 140°.
The sum of the interior angle and its corresponding exterior angle is 180°.

Therefore, the polygon has 9 sides. :)

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Length of side FD = c = $=\sqrt{(0-0)^2+(8-4)^2}\\=\sqrt{(0)^2+(4)^2}\\=\sqrt{0+16}\\=\sqrt{16}\\=4$

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s = a+b+c/2

s= 8.6+5.8+4/2

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