Question

What is the domain and range for `f(x)=7x+1`?

Answer 1

This is a Linear Function corresponding (graphically) to a straight line passing through `y=1` and with slope `m=7`.
It can accept all the Real `x` values giving, as output, all the possible Real values of `y`.
So:
Domain: all Real values of `x`;
Range: all Real values of `y`.