An isosceles triangle flower bed has a perimeter of 149 cm and a waist of 42 cm. What is the length of the base in cm?
一个等腰三角形的花坛，它的周长是149厘米，腰长是42厘米，底边长是多少厘米？
<gadget id="calculator">42 * 2</gadget>
<output>84</output>

<gadget id="calculator">149 - 84</gadget>
<output>65</output>

<result>65</result>