Data Handling and Statistics
Line of Best Fit
A line of best fit is a straight line drawn through a scatter plot that best represents the overall trend of the data. It can be used to estimate values and describe the relationship with an equation y = mx + c.
Estimating and Finding the Gradient
If a line of best fit has equation y = 3x + 5, then at x = 4, y = 3(4) + 5 = 17.
The gradient between two points on the line is found the same way as for any straight line: (y2 − y1) ÷ (x2 − x1).
Practice: Line of Best Fit
Estimate a value using a line of best fit, or find its gradient from two points.