The start of the lesson is used to review calculating the midpoints of line segments with different gradients. The development phase builds on this by deriving the equation of a straight line graph.

As learning progresses students use algebraic techniques to derive the equation of a line segment represented graphically and in the plenary, between two pairs of coordinates.

**Differentiated Learning Objectives**

- All students should be able to derive the equation of a positive straight line graph in the form y = mx + c
- Most students should be able to derive the equation of a straight line graph in the form y = mx + c
- Some students should be able to derive the equation of a straight line graph using two pairs of coordinates.

**Related Blogs**

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Equation of Straight Line Graphs