The base of a triangle is 20 meters and the height is 18 meters. What is the area of the triangle?
一个三角形底是20米，高是18米，这个三角形的面积是多少平方米．
<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">20 * 9</gadget>
<output>180</output>

<result>180</result>