Learn how to calculate the equation of a line from a graph, work out the gradient from an equation, and visualise intercepts with this step-by step guide.

Learn how to find equations of parallel lines, work out the gradient of perpendicular lines, and prove that given lines are parallel or perpendicular.

Calculating a Least Squares Regression Line: Equation, Example, Explanation If you want a simple explanation of how to calculate and draw a line of best fit through your data, read on!