I think you got confused how to use the squared thing..so I guess you mean this for number 1?
? So this is my answer if you got wrong.
1. 3x^2y + 5xy^3 + 9 / 3xy
= 3x^2y / 3xy + 5xy^3 / 3xy + 9/3xy
= x + 5y^2/3 + 3/xy
Answer: 3x + 5y^2 + 3/xy
2. a^2b^2c-6abc^2 + 5a^3b^5 / 2abc^2=
a^2b^2c/2abc^2 - 6abc^2 / 2abc^2 + 5a^3b^5 / 2abc^2
= ab / 2c - 3 + 5a^2b^4 / 2c^2
answer: ab/2c - 3 + 5a^2b^4/2c^2
3. (3x2 + 2x + 1) + (5x
2 - 7x) =
= 3x2 + 2x + 1 + 5x
2 - 7x
= 8x2 - 5x + 1