A right triangle rotates once around a right angle side. The diameter of the base of the formed cone is 10 cm and the height is 6 cm. What is the area of this right triangle in square centimeters?
一个直角三角形绕一条直角边旋转一周．形成的圆锥的底面直径为10厘米，高6厘米，这个直角三角形的面积是多少平方厘米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

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

<result>15</result>