An isosceles triangle with a base angle of 72° is called a golden triangle. What is the angle of the golden triangle.
底角是72°的等腰三角形被称为黄金三角形．黄金三角形的顶角是多少．
<gadget id="calculator">72 * 2</gadget>
<output>144</output>

<gadget id="calculator">180 - 144</gadget>
<output>36</output>

<result>36</result>