After enclosing an equilateral triangle frame with a 2-meter-long iron wire, there is still 20 centimeters left. What is the side length of this equilateral triangle frame?
用一根长2米的铁丝围成一个等边三角形框架后，还剩下20厘米．这个等边三角形框架的边长是多少？
<gadget id="calculator">2 * 100</gadget>
<output>200</output>

<gadget id="calculator">200 - 20</gadget>
<output>180</output>

<gadget id="calculator">180 / 3</gadget>
<output>60</output>

<result>60</result>