The length of one side of an isosceles right triangle is 2.5 cm, what is its area in cm**2.
一个等腰直角三角形的一条直角边长为2.5cm，它的面积是多少cm**2．
<gadget id="calculator">2.5 / 2</gadget>
<output>1.25</output>

<gadget id="calculator">2.5 * 1.25</gadget>
<output>3.125</output>

<result>3.125</result>