Answer:
infinite
Step-by-step explanation:
1/6 of 12 is 2
1/6 of 18 is 3
Plug them in
2z-3=2z-3
meaning you can put literally any number in place of z and it'd work.
infinite solutions
1/6 (12z - 18) = 2z - 3
2z - 3 = 2z - 3
0x = 0
