Question

given the following vector X, Find a non-zero sq matrix A where X = column [2 7 8] such as that AX=0

Answer 1

A square non-zero matrix eh?

Answer 2

Since it has to be orthogonal to the vector, I'd suppose it can't span all of \(\mathbb R^3\). So not all its rows would be linearly independent.

Answer 3

Here, find any vector orthogonal to \(\langle 2,7,8\rangle\) and just repeat it three times as the rows for our matrix. =)

Answer 4

ohhhh interesting! thank you so much! :)