The length of one side of an isosceles triangle is 8 cm, and the length of the base is 4 cm. What is the minimum length of rope needed to enclose this isosceles triangle?
一个等腰三角形的一条腰长8厘米，底边长4厘米，围成这个等腰三角形至少需要多少厘米长的绳子．
<gadget id="calculator">8 + 8 + 4</gadget>
<output>20</output>

<result>20</result>