# Equations of Straight-Line Graphs

Scheme of work: GCSE Higher: Year 9: Term 3: Equations of Straight-Line Graphs

#### Prerequisite Knowledge

• Recognise and describe linear number sequences, including those involving fractions and decimals, and find the term-to-term rule.
• Generate and describe linear number sequences

#### Success Criteria

• Plot graphs of equations that correspond to straight-line graphs in the coordinate plane;
• Use the form y = mx + c to identify parallel lines
• Find the equation of the line through two given points, or through one point with a given gradient
• Identify and interpret gradients and intercepts of linear functions graphically and algebraically

#### Key Concepts

• The gradient measures the rate of vertical change divided by horizontal change.
• Parallel lines have the same gradient
• The intercept always has the x value equal zero.

#### Common Misconceptions

• Students often confuse linear graphs with having the same notation as statistical graphs.
• The gradient can be calculated from any two points along the graph. Not necessarily from the origin.
• A linear function does not have to pass through the origin.
• It is beneficial to create a table of results when plotting a linear function. The coordinate pairs arise from the x and y values.

## Equations of Straight Line Graphs Resources

### Mr Mathematics Blog

#### 3D Vectors – Year 2

A-Level Scheme of work: Edexcel A-Level Mathematics Year 2: Pure 2: 3D Vectors

#### Parametric Equations

Edexcel A-Level Mathematics Year 2: Pure 2: Parametric Equations