There is a rectangular woodland, if the length is increased by 5 kilometers, the area will be increased by 15 square kilometers; if the width is increased by 6 kilometers, the area will be increased by 48 square kilometers. What is the area of this woodland in square kilometers?
有一块长方形林地，如果长增加5千米，面积就增加15平方千米；如果宽增加6千米，面积就增加48平方千米．这块林地的面积是多少平方千米？
<gadget id="calculator">15 / 5</gadget>
<output>3</output>

<gadget id="calculator">48 / 6</gadget>
<output>8</output>

<gadget id="calculator">3 * 8</gadget>
<output>24</output>

<result>24</result>