rectangle with a width of 2 cm has the same perimeter as a square with a side length of 4 cm. What is the side length of the rectangle in cm?
一个宽2厘米的长方形与一个边长4厘米的正方形周长相等，长方形的边长是多少厘米？
<gadget id="calculator">4 * 4</gadget>
<output>16</output>

<gadget id="calculator">16 / 2</gadget>
<output>8</output>

<gadget id="calculator">8 - 2</gadget>
<output>6</output>

<result>6</result>