I’m stuck on number 2, 3 and 4

To solve the system of equations below, grace isolated the variable y in the first equation and then substituted into the second equation. what was the resulting equation? 3y=12x x^2/4+y^2/9=1

What are the domain and range of the function f(x)=2^x+1

Write the equations in logarithmic form 9^4=6,561