Problem
COM-B1-M03-P008 Diagonals of a Polygon
#8
★★☆☆☆ Level 2 of 5
How many diagonals does a convex \(12\)-gon have?
Choose a pair of vertices and subtract sides.
Any two vertices determine a segment: \(\binom{12}{2}=66\). Among these are \(12\) sides. Therefore there are \(66-12=54\) diagonals.
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