If the two sides of a right triangle are 5 cm and 12 cm respectively, what is its area in square centimeters?
一个直角三角形的两条直角边分别是5厘米、12厘米，它的面积是多少平方厘米．
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">5 * 6</gadget>
<output>30</output>

<result>30</result>