Hi! I'm need some help with this question:
Decide $h$ so that the linear system $Ax=b$ has infinite solutions.
$$A=\pmatrix{
5 & 6 & 7 \cr
-7 & -4 & 1 \cr
-4 & 4 & 16 \cr}$$
$$b=\pmatrix{
6 \cr
30 \cr
h \cr}$$
I solved a similar question before but with A being a 2x2 matrix (and B a 2x1) and...