If the area of a rectangle is 9 square centimeters, what is the area of a triangle with the same base and height as it?
一个长方形的面积是9平方厘米，与它等底等高的三角形的面积是多少平方厘米．
<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<result>9/2 = around 4.5</result>