SOLUTION: How many interior angles does a undecagon have? How many diagonals can be drawn from each vertex of a decagon? How many distinct diagonals does a hexagon have?

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Question 202457: How many interior angles does a undecagon have?
How many diagonals can be drawn from each vertex of a decagon?
How many distinct diagonals does a hexagon have?
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
How many interior angles does a undecagon have?
Google says an undecagon has 11 sides.
So there are 11 interior angles.
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How many diagonals can be drawn from each vertex of a decagon?
A decagon has 10 sides.
Pick a vertex.
It has 2 sides going to adjacent vertices.
It can have 10-3= 7 diagonals drawn from the one vertex.
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How many distinct diagonals does a hexagon have?
A hexagon has seven sides.
Each pair of vertices determines a line segment.
There are 7C2 = 7*6/1*2 = 21 such line sements.
7 of those segments are sides of the hexagon.
There are 21-7 = 14 distinct diagonals.
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Cheers,
Stan H.