Solve the equation: 1x+2{x}=3(x); (2,3x+5(x)-49=0.
解方程：1x+2{x}=3(x)；(2,3x+5(x)-49=0．
<gadget id="calculator">19 / 3</gadget>
<output>19/3 = around 6.333333</output>

<result>19/3 = around 6.333333</result>