please help i need it for a quiz

Answer:
z=2
Step-by-step explanation:
I used cross multiplication to solve this.
2/9z=1/9
1(9z)=2(9)
9z=18
z=2
Answer= z=2
Step-by-step explanation:
its because 9 has a z next to it so we have to multiply the z, and we now the they simplified the fraction so we have 1/9, and why did i ay its z=2? because 9xz which is 2 is 18. sorry if my explination is terrible.