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Please Help. I will give a medal and fan you. In a quadrilateral, a student can draw two diagonals. In a pentagon, a student can draw five diagonals. In a hexagon, a student can draw nine different diagonals. How many diagonals can be drawn in a regular polygon that has 17 sides?
If there are n vertices or sides, then there will be \(\Large \frac{n(n-3)}{2}\) diagonals These pages may be of help http://www.mathsisfun.com/geometry/polygons-diagonals.html http://www.mathopenref.com/polygondiagonal.html