After cutting a circle into an approximate rectangle, the circumference is increased by 6 cm. What is the area of this circle.
将一个圆剪拼成一个近似的长方形后，周长比原来增加了6厘米．这个圆的面积是多少．
<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>