The perimeter of a rectangular garden is 36 meters. It is known that the length is twice the width. What is the area of the garden in square meters?
一个长方形花园周长是36米，已知长是宽的2倍，花园的面积是多少平方米？
<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<gadget id="calculator">36 / 2 / 3</gadget>
<output>6</output>

<gadget id="calculator">6 * 2</gadget>
<output>12</output>

<gadget id="calculator">12 * 6</gadget>
<output>72</output>

<result>72</result>