Answer:
A linear function is in the form y = mx + b or f(x) = mx + b, where m is the slope or rate of change and b is the y-intercept or where the graph of the line crosses the y axis. ... if your first diffs are the same it is linear. if not it is not linear.
a LINEar equation is an equation with a polynomial of degree 1 and is the graph of a LINE, let's look at this one, y = x² - 3, notice the exponent of ², meaning is a 2nd degree equation, and is a parabola, so is namely a quadratic, not a linear one.
