Help plz:

7. Add or subtract the following polynomials:

a. 5x^2 + 3y^3 – 4x^2 =

b. y^3 + 2y^3 – 8 + 2 =

c. 9 – 3x – 4x + 2x – 12 =

d. -6t + 4t^2 – 6 + 7t – 4t^2 =

Help plz:

7. Add or subtract the following polynomials:

a. 5x^2 + 3y^3 – 4x^2 =

b. y^3 + 2y^3 – 8 + 2 =

c. 9 – 3x – 4x + 2x – 12 =

d. -6t + 4t^2 – 6 + 7t – 4t^2 =

Step-by-step explanation: