If the side length of a square is increased by 2 cm, its area is increased by 16 cm2, what is the area of the original square in cm2?
一个正方形，如果边长增加2厘米，它的面积增加16平方厘米，原正方形的面积是多少平方厘米．
<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<result>9</result>