A right triangle, the two shorter sides are 8 decimeters and 10 decimeters respectively, what is its area in square decimeters?
一个直角三角形，较短的两条边分别是8分米和10分米，那么它的面积是多少平方分米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">8 * 5</gadget>
<output>40</output>

<result>40</result>