Question 908961
{{{(matrix(3,4,
5,-4,3,15,
6,2,9,13,
7,6,-6,6)
)}}}


(1/6)R2,(1/7)R3,(1/5)R1
{{{(matrix(3,4,
1,-4/5,3/5,3,
1,1/3,3/2,13/6,
1,6/7,-6/7,6/7)
)}}}


R2-R1; R3-R1
{{{(matrix(3,4,
1,-4/5,3/5,3,
0,17/15,9/15,-5/6,
0,58/35,-51/35,-15/21)
)}}}


{{{(matrix(3,4,
1,-4/5,3/5,3,
0,17/15,3/5,-5/6,
0,58/35,-51/35,-5/7)
)}}}


That is only a start.  Not yet finished.
(<s>The last two are not rendering and I do not know why</s>).