Question

What is the slope of the line below ?

Answer 1

Slope is rise over run, change in y over change in x.  Here we have points (1,3) and (3,9)

$\textrm{slope} = \dfrac{\textrm{change in y}}{\textrm{change in x}} = \dfrac{9-3}{3-1} = \dfrac{6}{2} = 3$

Answer: 3

That's checked by verifying the line goes up 3 for one to the right.  It does.