Cut a trapezoid into the largest triangle. If the upper and lower bases of the trapezoid are 12 cm and 28 cm respectively, and the height is 8 cm, find the area of the cut part.
将一个梯形剪成一个最大的三角形，若梯形的上下底分别是12厘米和28厘米，高是8厘米，求剪去部分的面积．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">12 * 4</gadget>
<output>48</output>

<result>48</result>