A polygon has 14 diagonals how many sides does it have?

To determine the number of sides in a polygon with 14 diagonals, we can use the formula for the number of diagonals in a polygon: D = n(n-3)/2, where n is the number of sides. By setting D = 14 and solving for n, we get n(n-3)/2 = 14. Simplifying this equation, we find that n^2 - 3n - 28 = 0. Factoring this quadratic equation, we get (n-7)(n+4) = 0. Therefore, the polygon has either 7 or -4 sides. Since the number of sides cannot be negative, the polygon must have 7 sides.