The perimeter of a rectangle is 49 cm, and the perimeter of a square is 13 cm less than the perimeter of the rectangle. What is the area of the square in square centimeters?
一个长方形的周长是49厘米，一个正方形的周长比这个长方形周长少13厘米，这个正方形的面积是多少平方厘米．
<gadget id="calculator">49 - 13</gadget>
<output>36</output>

<gadget id="calculator">36 / 4</gadget>
<output>9</output>

<gadget id="calculator">9 * 9</gadget>
<output>81</output>

<result>81</result>