Consider this example by my teacher:

CoursHeroTranscribedText:

10. Solve -x = 10 11 -31 11 -31 11 -31 11 31 Sy+2z 32 8y 2z 9 7 by using the inverse of the coefficient matrix 9 2 4 3 5 7 8 2 2 x z 9 9 2 The inverse of coefficient matrix will be given 4 5 6 10 solve 1 34 3 4 7 9 7 9 10 6 10 7 1 14 34 47 o O 6 10 o 47 0 O 2 5 2 14 34 10 6 10 11 -31 10 34 10 9 9 O 47 x 141 188 6 10 1 9 -14 7 34 9 10-9+6-7+1-9 11-9+ (31).7+34-9