If the two sides of a right triangle are 18 cm and 10 cm respectively, what is its area?
一个直角三角形的两条直角边分别是18厘米和10厘米，它的面积是多少．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">18 * 5</gadget>
<output>90</output>

<result>90</result>