The height of a parallelogram is 18cm, the area is 9cm**2, what is its base in cm?
一个平行四边形高是18cm，面积是9cm**2，它的底是多少cm．
<gadget id="calculator">9 / 18</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>