Linear Equations and Slope

Linear equations are a linear function whose graph is a line.
The standard form to write these equation is Ax+By=C where in A, B, and C are all integers.

Slope
Slope is Rise over Run, change in x over change in y, or y2-y1 over x2-x1. There are three forms to write slope in.
Slope intercept: y=mx+b This is probably the most common form which most people are more comfortable with. M= the slope and B= the y intercept
The previously mentioned standard form, which can be a bit hard to create.
Point slope: (y-y1)=m(x-x1) The point slope may be considered a bit harder by most, but it is very versatile as it can be transformed into slope intercept and standard form quite easily.
When there is a vertical line, the slope will be undefined. You can remember this if you imagine trying to ski down a vertical slope. You would fall and no one would be able to find you. Undefined.
Horizontal slopes are 0.
If two lines are parallel, they have the same slope. If two lines are perpendicular, they have opposite reciprocal slopes.