The base of the triangle is 8 meters and the height is 4.5 meters. Find its area.
三角形的底是8米，高是4.5米，求它的面积．
<gadget id="calculator">4.5 / 2</gadget>
<output>2.25</output>

<gadget id="calculator">8 * 2.25</gadget>
<output>18</output>

<result>18</result>