What is the solution of the one-dimensional linear equation 5x+15x=400 as X=
一元一次方程5x+15x=400的解为X=多少
<gadget id="calculator">5 + 15</gadget>
<output>20</output>

<gadget id="calculator">400 / 20</gadget>
<output>20</output>

<result>20</result>