A piece of iron wire can form a rectangle with a length of 19 cm and a width of 13 cm. If it is used to form a square, what is the side length of the square?
一条铁丝可以围成一个长19厘米，宽13厘米的长方形，如果用它围成一个正方形，正方形的边长是多少厘米？
<gadget id="calculator">19 + 13</gadget>
<output>32</output>

<gadget id="calculator">32 * 2</gadget>
<output>64</output>

<gadget id="calculator">64 / 4</gadget>
<output>16</output>

<result>16</result>