Gradient (Slope) of a Straight Line

The Gradient (also called Slope) of a straight line shows how steep a straight line is.

The method to calculate the gradient is:

Gradient  =

Change in Y Change in X

 

The gradient of the above line =	3 3	=  1
The gradient of the above line is equal to 1

Different Types

There are different types of gradients of a straight line. Below are listed most of the ones that you will come up against.

Remember:

• Starting from the left end of the line going across to the right is positive (but going across to the left is negative).
• Up is positive, and down is negative
  
  

		gradient =	3 5	=  0.6

	gradient =	4 2	=  2

	gradient =	-4 2	= –2

(That line goes down as you move along, so it has a negative gradient.)

	gradient =	0 5	=  0

(A line that goes straight across has a gradient of zero.)

	gradient =	3 0	= undefined

That last one is a bit tricky ... you can't divide by zero, so a "straight up and down" line's gradient is "undefined".