The length of a square is 9 cm and the width is 3 cm shorter than the length. What is the area of the rectangle in square centimetres.
一个正方形的长是9厘米，宽比长短3厘米．长方形的面积是多少平方厘米．
<gadget id="calculator">9 - 3</gadget>
<output>6</output>

<gadget id="calculator">9 * 6</gadget>
<output>54</output>

<result>54</result>