# Mathematics

The sum of interior angles of a regular polygon is 1080 degrees .What is the number of triangles the polygon can subdivide into

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1. 180(n-2) = 1080
n-2 = 6
n = 8
So the polygon has 8 sides and 8 vertices.
Each of the 8 vertices can form a triangle with 2 of the other 7 vertices.
8*6 = 48 triangles can be formed.
But some have been counted twice. How many?

google can provide some insights.

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oobleck
2. (2n-4)90, when n=6
1080=(2*6-4)90
1080=8*90
1080/72=

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