\(\boxed{\text{458.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\)
\[\textbf{а)}\ x^{2} - y^{2} = 0\]
\[(x - y)(x + y) = 0\]
\[y = x;\ \ y = - x\]
\[\textbf{б)}\ \frac{x^{2} - y}{x} = 0\]
\[x^{2} - y = 0;\ \ x \neq 0\]
\[y = x^{2};\ \ x \neq 0\]