If the upper base of a trapezoid is reduced by 3 cm, it becomes a square with a side length of 8 cm. What is the area of the trapezoid in square centimeters?
一个梯形上底减少3厘米后，是一个边长8厘米的正方形，梯形面积是多少平方厘米．
<gadget id="calculator">8 + 3 + 8</gadget>
<output>19</output>

<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">19 * 4</gadget>
<output>76</output>

<result>76</result>