Ineed to know how to set it up and how to solve the problem

For f(x) = 3x+1 and g(x) = x2 - 6, find (g/f)(x)

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

Alina fully simplifies this polynomial and then writes it in standard form. xy2 – 2x2y + 3y3 – 6x2y + 4xy2 if alina wrote the last term as 3y3, which must be the first term of her polynomial in standard form? xy2 5xy2 –8x2y –2x2y