The perimeter of an isosceles trapezoid is 24 cm, its upper base is 2 cm long, and its lower base is 8 cm long. What is the length of the waist of this isosceles trapezoid?
一个等腰梯形的周长是24厘米，它的上底长2厘米，下底长8厘米．这个等腰梯形的腰长是多少厘米？
<gadget id="calculator">24 - 2 - 8</gadget>
<output>14</output>

<gadget id="calculator">14 / 2</gadget>
<output>7</output>

<result>7</result>