You should divide or simplify the problem.
Answer: $0.35 which is the same as 35 cents
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Work Shown:
3 cookies = $1.05
3/3 cookies = $1.05/3
1 cookie = $0.35 = 35 cents
To use the elimination method, you have to create variables that have the same coefficient, then you can eliminate them.
The answer would be 7x+ 17