Obviously, a piece of iron wire is used to form a rectangle with a length of 18 cm and a width of 10 cm. If this wire is used to form a square, what is the side length of the enclosed square?
明明用一根铁丝围成了一个长18厘米，宽10厘米的长方形．如果用这根铁丝围成一个正方形，围成的正方形的边长是多少厘米？
<gadget id="calculator">18 + 10</gadget>
<output>28</output>

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

<gadget id="calculator">28 * (1/2)</gadget>
<output>14</output>

<result>14</result>