The perimeter of an isosceles trapezoid is 56 meters, the length of one side is 13 meters, and the height is 12 meters. Ask: What is the area of this trapezoid in square meters?
一个等腰梯形的周长是56米，一条腰长13米，高是12米，问：这个梯形的面积是多少平方米？
<gadget id="calculator">13 * 2</gadget>
<output>26</output>

<gadget id="calculator">56 - 26</gadget>
<output>30</output>

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

<gadget id="calculator">30 * 6</gadget>
<output>180</output>

<result>180</result>