If the base of a triangle is 5 decimeters and the height is 8 decimeters, what is its area?
一个三角形的底是5分米，高是8分米，它的面积是多少平方分米．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<result>20</result>