$$E_{1}:x^{2}=5$$
$x=-\frac{\sqrt{5E_{1}}}{5}$
$x=\frac{\sqrt{5E_{1}}}{5}\text{, }E_{1}\neq 0$
$E_{1}=5x^{2}$
$x\neq 0$
$x=\frac{\sqrt{5E_{1}}}{5}$
$x=-\frac{\sqrt{5E_{1}}}{5}\text{, }E_{1}>0$
