The lengths of the three sides of a triangle are 5, 6.5, and 6.5 respectively. If the length of the height on one side is 6, what is the area of the triangle?
一个三角形的三条边长分别是5、6.5、6.5，如果一条边上的高的长度是6，那么这个三角形的面积是多少．
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>15</result>