A rectangular vegetable field surrounded by a fence is 5 meters long and 3 meters wide. Now it is necessary to use this fence to form a square vegetable field. What is the side length of the square vegetable field?
一块用栅栏围成的长方形菜地，长是5米，宽是3米，现要用此栅栏围成一个正方形菜地，该正方形菜地的边长是多少米？
<gadget id="calculator">5 + 3</gadget>
<output>8</output>

<gadget id="calculator">2 / 4</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">8 * (1/2)</gadget>
<output>4</output>

<result>4</result>