Find all distinct eigenvalues of A. Then find the basic eigenvectors of A corresponding to each eigenvalue.
For each eigenvalue, specify the number of basic eigenvectors corresponding to that eigenvalue, then enter the eigenvalue followed by the basic eigenvectors corresponding to that eigenvalue.

Find all distinct eigenvalues of A. Then find

A = [ 3 9 -20 ]
[ 0 16 -30]
[ 0 9 -17]