One angle of an isosceles triangle is a right angle, and the sum of the two sides is 12 decimeters. What is its area?
一个等腰三角形有一个角是直角，两条直角边的和是12分米，它的面积是多少平方分米．
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">6 * 3</gadget>
<output>18</output>

<result>18</result>