For a rectangle, its width increases by 2 cm, its area increases by 8 cm2, and it just becomes a square. What is the area of the original rectangle?
一个长方形，他的宽增加2厘米，面积增加8平方厘米，正好变成一个正方形，原来的长方形面积是多少？
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 - 2</gadget>
<output>2</output>

<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<result>8</result>