Find the measure of each interior angle of a regular octagon.
a 135
b 1,080
c 180
d100

find the sum of the interior angles of a nonagon.

a 140
b 1,620
c 1,260
d 1,450

ok, here the formula measure of each interior angle of regular n-gon

octagon ~ 8-gon, so

180° - 360°/8 = 135° (A)

for the sum, we just need multiply the formula above with n

nonagon ~ 9-gon

sum = 9(180° - 360°/9)

= 9(140°) = 1260 (C)

okay wait before i answer, is this for your points on a graph?

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