Final answer:
The polygon has 6 sides.
Step-by-step explanation:
A triangle is a three-sided polygon. The sum of the interior angles of a triangle is always 180°. So, if the sum of the interior angle measures of a triangle is 720°, we can use the formula 180° x (n - 2) to find the number of sides (n) of the polygon. Solving the equation:
180° x (n - 2) = 720°
n - 2 = 720° ÷ 180°
n - 2 = 4
n = 4 + 2
n = 6
Therefore, the polygon has 6 sides.