Find the real eigenvalues of the matrix $$A=\left[\begin{array}{cccc} -5 &3 &8 &0\cr 4 &-6 &0 &10\cr -3 &3 &3 &-3\cr 3 &-3 &-2 &4 \end{array}\right].$$ The real eigenvalues are . (Enter your answers as a comma separated list.)