Answer:
The difference between 18 and seven times a number: 18 - 7x
Explanation:
(ii) One more than the difference between 18 and seven times a number:
Add 1 to the expression from step (i) and get
1 + (18 - 7x)
(iii) One more than the difference between 18 and seven times a number is -9:
Set expression from step (ii) equal to -9 and get
1 + (18 - 7x) = -9
You can simplify and solve for x.