Which of the following functions is not linear a: f(x)=2x^3 b: f(x)=14x+7 c: f(x)=8 d: f(x)=2/3-1/2x

A: f(x)=2x^3

To put it in simple terms, this is a quadratic function. I know this because there is an exponent in this given function. In the future, you can discern for yourself whether or not the given options are linear since something as simple as this is easy to pick up and utilize.

a is the correct

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.