The phrase would be: "z divided by the difference of 8 and 9"
First, let's fine the decimal of each fraction.
-5 Divided By 6 = -0.83333333333
17 Divided By 18 = 0.94444444444
-2 Divided By 9 = -0.22222222222
-5/6 - 17/18 - (-2/9) = -1.55555555556
Answer:
the set of whole number since it is defined as positive integers + zero
(2,1) is the correct answer