A piece of iron wire can enclose a rectangle with a length of 6 cm and a width of 2 cm. If this wire is surrounded by a square, what is the side length of the square?
一根铁丝能围成长6厘米，宽2厘米的长方形，如果把这根铁丝围成正方形，正方形的边长应是多少厘米？
<gadget id="calculator">6 + 2</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>