Simplify the Matrix [[1,0,2,7],[0,1,-2,5],[0,0,0,-3]]

$[\begin{array}{c} 1 & 0 & 2 & 7 \\ 0 & 1 & - 2 & 5 \\ 0 & 0 & 0 & - 3 \end{array}]$

Substitute in each matrix definition.

$[\begin{array}{c} 1 & 0 & 2 & 7 \\ 0 & 1 & - 2 & 5 \\ 0 & 0 & 0 & - 3 \end{array}]$