Question

Is the function g(x)=
7
9
x linear or nonlinear?

Answer 1

If g(x) = (7/9)x, it is linear — it has the form g(x) = mx + b with m = 7/9 and b = 0 (a straight line through the origin).

If you meant g(x) = 7/(9x) instead, that is nonlinear (it’s a reciprocal function).