Question 1085210
{{{ x + x^2 = 4 + 2x }}}
{{{ x^2 - x - 4 = 0 }}}
{{{ x = (-(-1) +- sqrt(  (-1)^2 - 4*(1)*(-4))) / 2 }}}
{{{ x =  1/2 +- sqrt(17) / 2 }}}

Solutions:   {{{ x = (1+sqrt(17)) / 2 }}} and {{{ x = (1-sqrt(17))/2 }}}