How would i solve for x in the matrix equation.
x 0 0
0 x 0 = 0
0 0 x
You should be able to know that the you are multiplying x with a $\displaystyle 3 \times 3$ identity matrix.
$\displaystyle \left(\begin{array}{ccc}x&0&0\\0&x&0\\0&0&x\end{ar ray}\right)=
x \times \left(\begin{array}{ccc}1&0&0\\0&1&0\\0&0&1\end{ar ray}\right)= 0 $
So, what can you say about x?