Given that the two sides of an isosceles triangle are 6 cm and 12 cm, what is its perimeter in cm?
已知一个等腰三角形的两条边是6厘米和12厘米，它的周长是多少厘米？
<gadget id="calculator">6 + 6 + 6 + 6 + 6</gadget>
<output>30</output>

<result>30</result>