SOLUTION: An octagon has angles that measure 140°, 140°, 130°, 130°, 150°, 145°, 115°, and d. What is d?

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Question 831482: An octagon has angles that measure 140°, 140°, 130°, 130°, 150°, 145°, 115°, and d. What is d?
Found 2 solutions by Fombitz, KMST:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
An octagon's angles sum to 8%2A180=1080
140%2B140%2B130%2B130%2B150%2B145%2B115%2Bd=1080
Solve for d

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
The measures of the interior angles of any polygon with n sides add up to
%28n-2%29%2A180%5Eo .
An octagon has 8 sides.
The measures of the interior angles of any octagon add up to
%288-2%29%2A180%5Eo=6%2A180%5Eo=1080%5Eo
So,
140%5Eo%2B1400%5Eo%2B1300%5Eo%2B1300%5Eo%2B1500%5Eo%2B1450%5Eo%2B1150%5Eo%2Bd=1080%5Eo
950%5Eo%2Bd=1080%5Eo
d=1080%5Eo-950%5Eo
highlight%28d=130%5Eo%29