This deep dive covers Common Types of Straight Line Graphs within Straight Line Graphs for GCSE Mathematics. Revise Straight Line Graphs in Graphs for GCSE Mathematics with 14 exam-style questions and 20 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 7 of 8 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Common Types of Straight Line Graphs
| Type | Equation Form | Example | Key Features |
|---|---|---|---|
| Through origin | y = mx | y = 3x | Passes through (0, 0) |
| Horizontal line | y = c | y = 5 | Gradient = 0, parallel to x-axis |
| Vertical line | x = c | x = 3 | Undefined gradient, parallel to y-axis |
| Positive gradient | y = mx + c (m > 0) | y = 2x + 1 | Line slopes upward left to right |
| Negative gradient | y = mx + c (m < 0) | y = -x + 3 | Line slopes downward left to right |
Practice questions for Straight Line Graphs
A straight line has the equation y = 3x + 7. What is the gradient of this line?
Line A has equation y = 3x + 1. Line B has equation y = 3x - 5. Explain why lines A and B are parallel. Include the values of their gradients in your answer.
Quick recall flashcards
What is the y-intercept?
The point where the line crosses the y-axis, found when x = 0.
What is a linear relationship?
A relationship where one variable changes at a constant rate with respect to another, producing a straight line graph.