A rectangle, if the length remains the same, but the width increases by 5 meters, the area increases by 35 square meters. At this time, it just becomes a square, find the area of the original rectangle.
一个长方形，如果长不变，宽增加5米，面积就增加35平方米．这时正好变成了一个正方形，求原来长方形的面积．
<gadget id="calculator">35 / 5</gadget>
<output>7</output>

<gadget id="calculator">7 - 5</gadget>
<output>2</output>

<gadget id="calculator">7 * 2</gadget>
<output>14</output>

<result>14</result>