If the width of a rectangle remains the same, the length increases by 8 meters, and the area increases by 72 square meters; if the length remains the same, but the width decreases by 4 meters, the area decreases by 48 square meters. What is the original area of the rectangle in square meters?
一个长方形如果宽不变，长增加8米，面积增加72平方米；如果长不变，宽减少4米，面积就减少48平方米．那么这个长方形的原来面积是多少平方米．
<gadget id="calculator">48 / 4</gadget>
<output>12</output>

<gadget id="calculator">72 / 8</gadget>
<output>9</output>

<gadget id="calculator">12 * 9</gadget>
<output>108</output>

<result>108</result>