An operation is now stipulated: x△y=3x-2y. If x△(4△1)=7, then x=how much.
现规定一种运算：x△y=3x-2y．如果x△(4△1)=7，那么x=多少．
<gadget id="calculator">20 + 7</gadget>
<output>27</output>

<gadget id="calculator">27 / 3</gadget>
<output>9</output>

<result>9</result>