If the two sides of a right triangle are 3cm and 5cm respectively, what is the area of the triangle in square centimeters?
一个直角三角形的两条直角边分别是3cm和5cm，那么这个三角形的面积是多少平方厘米．
<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">3 * (5/2)</gadget>
<output>15/2 = around 7.5</output>

<result>15/2 = around 7.5</result>