If an isosceles triangle has two sides whose lengths are 5cm and 2cm, what is its perimeter in cm?
一个等腰三角形，其中的两条边的长度是5cm和2cm，则它的周长是多少cm．
<gadget id="calculator">5 + 5 + 2</gadget>
<output>12</output>

<result>12</result>