SOLUTION: one exterior angle of a convex polygon is 40 degree and each of the others is equal to 20 degree. how many sides has the polygon?

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Question 1002849: one exterior angle of a convex polygon is 40 degree and each of the others is equal to 20 degree. how many sides has the polygon?
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
Sum of exterior angles of any convex polygon = 360 degrees

Letting a be the number of total vertices ("angles") of the polygon, we have

40 + 20(a-1) = 360 (note: a-1, not a)

a = 17

So 17 sides.