trying to figure out if this is true, and why?
asked Dec 9, 2012 in Geometry Answers by anonymous

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2 Answers

It is not true.

The sum of the degrees in a triangle (on a flat surface) is 180.

The number of edges in a triangle is 3, twice that number would be 6.

6 does not equal 180.
answered Aug 31, 2014 by johnperkins Top Rated User (103,080 points)
The degree of a vertices is how many edges are coming out of it. So, for a triangle, the sum of the degrees of a triangle is 180, but the sum of the degrees of the vertices of a triangle is (2+2+2) 6. Being that there are 3 edges, the sum of the degrees of the vertices (6) is exactly double the number of edges.
Looked it up...graph theory.  Was thinking geometry due to the category the question was posted in.  I stand corrected.

The sum degrees of all the vertices would be twice the number of edges because each edge has to have a start and an end.  Introducing 1 edge introduces 2 endpoints, which makes 2 degrees.
Every edge is connected to exactly two vertices.
answered Apr 20 by shannonneol97 (140 points)

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