How can you verify the slope of a line just by looking at its graph? Think rise over run. Slope is a ratio between the change in y and the change in x. In fact, slope is written in the following format:
Refer to the image of the graph of y= 1/2x + 2 and choose a couple of points on the line.
Point A (-4,0) and Point B (0,2)
Start with the rise. Put your finger on Point A and count
up until you are across from Point B. You moved up 2
units; rise is 2.
Continue with the run. Move your finger to the right
until you are at Point B. You moved across 4 units;
run is 4.
Therefore: rise/run = 2/4.
Simplify and discover that the slope of the line is 1/2.
Quick tip for rise: Move your finger up, and rise is positive. Move your finger down, and rise is negative.
Quick tip for run: Move your finger to the right, and run is positive. Move your finger to the left, and run is negative.