The sum of the interior angles of a triangle is 180°, the sum of the interior angles of a quadrilateral is (4-2)*180°, what is the sum of the interior angles of a hexagon.
三角形的内角和是180°，四边形的内角和是(4-2)*180°，六边形的内角和是多少．
<gadget id="calculator">6 - 2</gadget>
<output>4</output>

<gadget id="calculator">4 * 180</gadget>
<output>720</output>

<result>720</result>