\[- y^{3} = ( - y)^{3}\text{\ \ \ }\]
\[\ y - 4:\]
\[- ( - 4)^{3} = 4^{3} = 64;\]
\[\left( - ( - 4) \right)^{3} = 4^{3} = 64.\]
\[- y^{3} = ( - y)^{3}\text{\ \ \ }\]
\[y = 0:\]
\[- 0^{3} = 0;\ \ \]
\[( - 0)^{3} = 0.\]
\[- y^{3} = ( - y)^{3}\text{\ \ \ \ }\]
\[y = 5:\]
\[- 5^{3} = - 125;\]
\[( - 5)^{3} = - 5^{3} = - 125.\]