If the length of one side of an isosceles right triangle is 9 cm, what is its area in square centimeters?
一个等腰直角三角形的一条直角边的长是9厘米，它的面积是多少平方厘米．
<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">9 * (9/2)</gadget>
<output>81/2 = around 40.5</output>

<result>81/2 = around 40.5</result>