Step-by-step explanation
In simple terms, A linear function is a function that makes a straight line when graphed. Thus non-linear functions are any functions that are not linear.
linear functions follow the standard equation of a line, which is called "slope-intercept form
Linear function: A function that is a straight line and has a degree of 1
Non-linear function: A function that is not a straight line and has a degree other than 1
So for the given question, we are told to select two equations that are non-linear
option A: y= x+4 is a linear equation because it has a degree of 1
option B: y=x³-2x is a non-linear equation because the function has a degree higher than 1. It is a cubic function
option C: 2x +4y =8 is a linear equation because its graph is a straight line and has a degree of 1
Option D: y=2x²+4x-8 is not a linear equation because it has a degree of 2