The slope is an expression of the change in y after a change in x.
Usually, this is expressed with a ratio, with the difference in y first.
The formula for slope is written as [tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex].
Our points are [tex](x_1,\ y_1)[/tex] and [tex](x_2,\ y_2)[/tex].
Of course, the difference is just subtracting one from the other, but you'll get either a positive or negative value depending on which way you subtract. That's all fine and dandy if you handle the differences in x and y in the same way like in the formula, because any unwanted negatives get cancelled out...it's not important.
Anyways, let's plug our points (2, 8) and (6, 12) into the slope formula.
[tex]\frac{12-8}{6-2}=\frac{4}{4}=\frac{1}{1}[/tex]
Any number divided by 1 stays the same, so we can leave out the /1 and just have our slope be 1.
