I dont get how i know if this is linear or not f(-4)=2 or f(4)=-7 plz explain well?

Question

;[

Answer 1

The first of the original equations is linear by definition since the highest power on the x in the equation is 1. However, the second is not linear, though the graph of the equation is a horizontal line. Since there is no x term, we know that the power on that term must be 0, which is the case in a constant function. The reason that the term constant is used is because no matter what value x is put into the function, y is always the same. In this case, it is 2.

Answer 2

I know there's a more technical mathematical definition of linearity, but for your purposes, a function f(x) is "linear" if it's graph is a straight line.  This occurs when either f is a polynomial of degree 0 or 1.

A polynomial of degree 0 has the form:

f(x) = Constant

A polynomial of degree 1has the form:

f(x) = Ax + B, where A and B are constants