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Graph Gallery

Walk the gallery of graphs: read coordinates, decode y = mx + c for gradient and intercept, spot parallel lines, and recognise every shape from a straight line to a parabola, cubic and reciprocal.

⏱️ 16 min 🎯 16 activities Teachers Not yet rated Students Not yet rated

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What you'll cover

Graph Gallery 🖼️

Every graph tells a story with a picture. In this gallery you will learn to read the **straight line** (y = mx + c) and to recognise the famous **curves** at a glance. Two skills carry most of the marks: pulling the **gradient** and **intercept** out of a line, and matching a **shape** to its equation.

Coordinates 📍

A point is written **(x, y)**: the first number is how far **across** (x), the second how far **up** (y). Both axes run negative as well as positive, giving **four quadrants**. So (3, −2) means 3 right and 2 down. Read across before up — "along the corridor, then up the stairs".

Plot the coordinate

An interactive activity.

The straight line: y = mx + c 📈

Every straight line can be written **y = mx + c**: • **m** is the **gradient** — how steep the line is. • **c** is the **y-intercept** — where the line crosses the y-axis. For **y = 2x + 3**, the gradient is 2 and the line crosses the y-axis at 3. Read them straight off the equation.

Gradient = rise over run 📐

The **gradient** measures steepness: **gradient = rise ÷ run** (how much it goes **up** for each step **across**). • A line going **uphill** left-to-right has a **positive** gradient. • A line going **downhill** has a **negative** gradient. It is rise ÷ run — never run ÷ rise. Up over across.

Gradient from two points

An interactive activity.

Find the y-intercept

For the line y = 3x − 4, where does it cross the y-axis (the value of c)?

  • −4
  • 3
  • 4
  • 0

Read the gradient

An interactive activity.

Parallel lines ⏸️

Two lines are **parallel** when they have the **same gradient** — the same value of **m**. Their intercepts (c) can differ; only the steepness must match. So y = 2x + 1 and y = 2x − 3 are parallel (both gradient 2), but y = 3x + 1 is not.

Which line is parallel?

Which of these lines is parallel to y = 2x + 1?

  • y = 2x − 3
  • y = 3x + 1
  • y = −2x + 1
  • y = ½x + 1

The shapes of graphs 🎨

Not every graph is a line. Learn these four silhouettes: • **Linear** (y = mx + c) — a straight line. • **Quadratic** (y = x²) — a U-shaped **parabola**. • **Cubic** (y = x³) — an S-shaped curve. • **Reciprocal** (y = 1/x) — two separate curved branches.

Find the parabola

An interactive activity.

Match each equation to its graph shape

  • y = 2x + 1
  • y = x²
  • y = x³
  • y = 1/x
  • A straight line
  • A U-shaped parabola
  • An S-shaped cubic curve
  • A reciprocal with two branches

Name the shape

What shape is the graph of y = x² − 4?

  • A parabola (U-shaped)
  • A straight line
  • An S-shaped cubic
  • A reciprocal curve

Order the method

An interactive activity.

The equation of a line

A straight line has equation y = mx + c. The letter m is the _____, found as rise ÷ run, and the letter c is the _____, where the line crosses the y-axis. Two lines are parallel when they have the same _____.

gradient y-intercept gradient origin root