If the upper base of a right-angled trapezoid is extended by 5 cm, a square with a side length of 12 cm can be obtained. What is the area of this rectangular trapezoid.
如果把一个直角梯形的上底延长5厘米就可以得到一个边长是12厘米的正方形．这个直角梯形的面积是多少．
<gadget id="calculator">12 + 7</gadget>
<output>19</output>

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

<gadget id="calculator">19 * 6</gadget>
<output>114</output>

<result>114</result>