Question

Solve the following.
$5z^2-30=0$

Answer 1

$5z^2-30=0$

$\Rightarrow$ $5(z^2-6)=0$

$\Rightarrow$ $z^2-6=0$

$\Rightarrow$ $z^2=6$

$\Rightarrow$ $z=\pm \sqrt{6}$

$\therefore$ $z=\sqrt{6},-\sqrt{6}$