I really need help with this question...

I need to find the elementary matrice so that:

EB=C

B = $\displaystyle \[ \left( \begin{array}{ccc} 1 & 4 & 3 \\ 0 & 0 & 1 \\ 0 & -6 & -6 \end{array} \right)\]$

C = $\displaystyle \[ \left( \begin{array}{ccc} 1 & 4 & 3 \\ 0 & 0 & 1 \\ 0 & 1 & 1 \end{array} \right)\]$

This is what i've tried

Row 3 <-- -1/6R3 (Doesn't work...)

Any other methods don't work since they add different values..

Can someone help me out here please?

I've spent an hour on this question already