rectangle with a length of 8 cm and a width of 4 cm is exactly surrounded by a piece of iron wire. If this wire is used to form a largest square, what is the area of the square in square centimeters?
用一根铁丝正好围成一个长8cm，宽4cm的长方形，如果用这根铁丝围成一个最大的正方形，这个正方形的面积是多少平方厘米．
<gadget id="calculator">8 + 4</gadget>
<output>12</output>

<gadget id="calculator">12 * 2</gadget>
<output>24</output>

<gadget id="calculator">24 / 4</gadget>
<output>6</output>

<gadget id="calculator">6 * 6</gadget>
<output>36</output>

<result>36</result>