Use a lead wire with a length of 26 cm to make a quadrilateral. When the length and width are how many centimeters respectively, the area of the quadrilateral will be the largest.
用长26厘米的铅丝做一个四边形，当长、宽各是多少厘米时，所做成的四边形面积最大．
<gadget id="calculator">26 / 4</gadget>
<output>13/2 = around 6.5</output>

<result>13/2 = around 6.5</result>