if a > 0, there are two possible solutions:
[tex]x^{2} = a\\\sqrt{x^{2} } = \sqrt{a} \\[/tex]
the square root of a square is the base in absolute value bars
[tex]|x| = \sqrt{a}[/tex]
[tex]x = -\sqrt{a} ; x = \sqrt{a}[/tex]
if a = 0, that means x = 0. anything multiplied by 0 is 0
if a < 0, there are no solutions because anything squared has to be positive
