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Re: External Angle definition 
Posted:
Oct 30, 2006 9:23 AM


DEFINITION 1. Interior angle at the vertex A is called the angle defined by the two sides through A. Clearly, for each vertex of a polygon there are two interior angles of opposite sence and equal measure. DEFINITION 2. Exterior angle at the vertex A is called the angle defined by one side through A and the extension of the other. Clearly, for each vertex of a polygon there are two exterior angles of opposite sence. THEOREM 1. Each exterior angle is supplementary to its corresponding iterior. THEOREM2. The sum of all interior angles of the same sence of an ngon is equal to (2*n4)r. THEOREM2. The sum of all exterior angles of the same sence of an ngon is equal to 4r.



