Key Concepts in Straight-Line Graphs
- Gradient of a straight line
- y = mx + c
- Finding the equation of a line
- Parallel and perpendicular lines
- Midpoint and distance between two points
Exam Tips for Straight-Line Graphs
- 💡Gradient = rise ÷ run = (y₂−y₁)/(x₂−x₁)
- 💡Parallel lines have the same gradient
- 💡Perpendicular lines: gradients multiply to −1
Exam Board Coverage
Straight-Line Graphs appears on all major GCSE Maths exam boards at both Foundation and Higher tier.
AQA
Edexcel
OCR
Frequently Asked Questions
How do I find the equation of a straight line?
Find the gradient m using two points, then substitute one point into y = mx + c to find c.
How do I find a perpendicular gradient?
If the original gradient is m, the perpendicular gradient is −1/m (the negative reciprocal).