After converting a circle into a rectangle, the circumference of the rectangle is 6 cm longer than the circumference of the circle. What is the area of the original circle in square centimeters?
把一个圆转化成长方形后，长方形的周长比圆的周长多6厘米，原来圆的面积是多少平方厘米．
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9</gadget>
<output>28.26</output>

<result>28.26</result>