x

-2

-1

0

1

2

y

-7

-4

-1

2

5

is this a function and non linear

This is a function because each input x corresponds to exactly one output y. However, this is a linear function because the relationship between x and y is given by a straight line.

is it linear or non linear

Apologies for the confusion in my previous response. This is a linear function because the relationship between the input x and the output y is given by a straight line.