Respuesta :

Answer: D. y = x^2

Step-by-step explanation:

Linear functions are functions in which the power of the unknown variable is 1 , that is the other of the unknown variable will be 1

A. y = x

This is a linear function because both x and y has 1 has their power

B. y = 2x

This is also linear

C. y = x + 2

This is also linear

D. y = x^2

This is not linear , although the power of y is 1 but the power of x is 2 , for it to be linear , the highest power of the unknown must be 1