A triangle whose base is 7 cm long and whose height is twice that of the base, what is the area of the triangle in square centimeters?
一个三角形，它的底边长是7厘米，高是底边的2倍，这个三角形的面积是多少平方厘米．
<gadget id="calculator">7 * 2</gadget>
<output>14</output>

<gadget id="calculator">14 / 2</gadget>
<output>7</output>

<gadget id="calculator">7 * 7</gadget>
<output>49</output>

<result>49</result>