Problem $3$: Try using an inverse to solve the system

$3x_1-x_2+3x_3-x_4=7$

$-x_1-x_2+x_4=-10$

$2x_1-2x_2+3x_3=-3$

$5x_1-3x_2+6x_3-x_4=4$

$($it won't work$).$ Copy$/$past the Octave code and the error$/$warning message you get with the output, and describe in a couple sentences what the trouble is now $-$ can you tell from this information alone whether or not there is a solution and what type it is$?$ Then use a different approach to definitively solve it and write the solution if there is one.