Hi,
3x + 5y – z = 2
-x – 8y + 3z = -6 |multipling 1st EQ by 8, 2nd by 5 and adding EQs to eliminate y
24x - 8z = 16
-5x +15z = -30
19x + 7z = -14
z = 2/3x
19x + 14/3x = -14 ||Multiplying thru by 3 so as all denominators = 1
71x = -42
x = -42/71 , z = -28/71
substitute x and z into 1st EQ to find y =