Pearson Edexcel International GCSE in Mathematics (Specification A) · 4MA1 · Free · no account needed

Coordinate Geometry

y = mx + c, gradients, midpoints and lengths — then parallel and perpendicular lines at Higher Tier.

Every lesson here ends the same way: learn it, teach it to an AI pupil who asks the awkward question, then defend it against the thinker with the strongest claim on it — free · no account needed.

2 modules of Pearson Edexcel International GCSE Mathematics (1 Higher Tier), each explained in full — what it is, why it works, when a question is asking for it, the mistakes that cost marks and worked examples — with five graded questions marked on your own device. Completely free.

The modules in Coordinate Geometry

Straight Lines: y = mx + c

Gradient as a rate of climb, intercept as the starting height — and building a line's equation from any two of its points. Every non-vertical straight line is y = mx + c: m is the gradient (how much y climbs when x increases by 1) and c is the y-intercept (the height where the line crosses the y-axis).

When a question is asking for it: Reading real graphs (m is a speed, a price per unit, a rate); 'find the equation of the line through…' questions; and as the foundation for parallel/perpendicular work and linear modelling. Learn Straight Lines: y = mx + c →

Parallel & Perpendicular Lines (Higher Tier)

Same gradient means parallel; gradients multiplying to −1 mean perpendicular — and the constructions that follow. Higher Tier. Parallel lines share a gradient (same climb, different start).

When a question is asking for it: 'Parallel to … through …' and 'perpendicular to … through …' equation-building; perpendicular bisectors (midpoint + perpendicular gradient); and tangent/radius questions in circle work… Learn Parallel & Perpendicular Lines →

The mistakes that cost marks in Coordinate Geometry

One from each module — the error examiners see most, with the module that puts it right.

• Gradient as run over rise. It's rise OVER run — vertical change divided by horizontal change. (Straight Lines: y = mx + c)
• Perpendicular gradient as just the negative: perpendicular to 2 is −1/2, not −2. Flip AND negate. (Parallel & Perpendicular Lines)

Where Coordinate Geometry sits in the specification

Content area 3 of 4MA1, sub-topic 3.3. Incandio is aligned to the specification and is not published by Pearson; the numbers are given so you can check every module against your own copy.

• 3.3 — Graphs — parallel and perpendicular gradients (Higher)

How Coordinate Geometry is mastered on Incandio

Every module above ends the same way: five questions that climb Grade 6 → 9+, then you teach the method back to Ember, an AI pupil who asks the awkward question, and defend it against the mathematician with the strongest claim on it. Exam Ready carries 18 authored exam-style questions across this strand, marked on Incandio.

All of Incandio Mathematics · The 4MA1 specification · Exam Ready