square flower bed needs to walk 20 meters to walk around the flower bed. What is the side length of the flower bed?
一个正方形的花坛，围绕这个花坛走一圈要走20米，这个花坛的边长是多少米．
<gadget id="calculator">20 / 4</gadget>
<output>5</output>

<result>5</result>