y = Mx + b is the standard form of a linear equation.
M is the slope or Rise (the difference in the y values) divided by the Run (the difference in the x values).
The y-intercept b is a starting place for graphing a linear equation it is in the form of (0,b). Keep the plus or minus sign before it on the standard equation. start at (0,b) and count up or down the rise the top number of the slope and then count across in the positive (to the right) or the negative (to the left) the run or bottom number of the slope. This gives you two points and you can draw a line to create the graph. If the slope is positive the line will rise, negative it will go down.