The [b]gradient[/b] of a line is a measure of its steepness. The gradient of the line passing through [math]A\left(x_A,y_A\right)[/math] and [math]B\left(x_B,y_B\right)[/math] is [math]\frac{y-steep}{x-steep}=\frac{y_B-y_A}{x_B-x_A}[/math][br][br]In the next applet, move A and B and watch how the gradient of the line changes.
Describe what needs to happen in order for the gradient to be negative.
Explain why the gradient of a horizontal line is 0.
What happens with the gradient when the line is vertical? Why do you think this happens?
The [b]gradient[/b] of the line passing through [math]A\left(x_A,y_A\right)[/math] and [math]B\left(x_B,y_B\right)[/math] (with [math]x_A\ne x_B[/math]) is [math]m=\frac{y_B-y_A}{x_B-x_A}[/math]