Answer:
1/3y-7
Step-by-step explanation:
For these kinds of problems you want to combine like terms. 2/3y and -1/3y are like terms, and when adding them together, or subtracting 1/3y from 2/3y, you get 1/3y. -3 and -4 are like terms, and adding them together gives you -7. The final expression can be written as 1/3y-7.