There is a rectangle surrounded by wire, 7 decimeters long and 5 decimeters wide. If it is changed into a square, what is the side length of this square?
有一个用铁丝围成的长方形，长7分米，宽5分米．如果改围成一个正方形，这个正方形的边长是多少分米？
<gadget id="calculator">7 + 5</gadget>
<output>12</output>

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

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

<result>6</result>