Let $T$ be the linear transformation defined by

$T(x_1,x_2,x_3,x_4, x_5) = 2 x_1+ 6 x_2- x_3 - 8 x_4 - 9 x_5$.

Its associated matrix $A$ is an $n\times m$ matrix,

where $n=\,$ , and $m=\,$ .