$\begin{array}{1 1}16x^2+25y^2+25z^2+225=0 \\9x^2+25y^2+25z^2-225=0 \\ 9x^2+25y^2+25z^2+225=0 \\16x^2+25y^2+25z^2-225=0 \end{array} $