Answer:
z = -4.
Explanation:
-9x-14z=128
22x+19z=-252
From the first equation:
-9x = 14z + 128
--> x = -(14z + 128)/ 9
Now we substitute for x in the second equation:
22 *-(14z + 128)/ 9 + 19z = -252
Multiply through by 9:
22(-14z - 128) + 171z = -2268
---> -308z - 2816 + 171z = -2268
---> -137z = -2268 + 2816
---> -137z = 548
---> z = -4.