GCSE Maths

Algebra
revision.

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Linear equations, quadratics, simultaneous equations and graphs, built on the balance method rather than shortcuts.

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05

The quadratic formula

GCSE Maths quadratic formula: write a, b and c including signs, compute the discriminant, keep the ± until the last line, and round only when the question asks.

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06

Completing the square

GCSE Maths completing the square: rewrite x² + bx + c as (x + p)² + q, read the turning point, and handle a ≠ 1 by factoring a out first.

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07

Inequalities on a line

GCSE Maths inequalities: solve linear inequalities with the balance method, reverse the sign when multiplying or dividing by a negative, and show the answer on a number line.

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08

Nth term of linear sequences

GCSE Maths linear sequences: find the common difference, write the nth term as an + b, and use it to generate terms or to decide whether a number is in the sequence.

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09

Changing the subject of a formula

GCSE Maths changing the subject: use inverse operations in reverse order, including squares, fractions and brackets, and factorise when the new subject appears twice.

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10

Factorising quadratics

GCSE Maths factorising quadratics: highest common factor first, then two brackets for x² + bx + c, and grouping when a ≠ 1 — expand every time as a check.

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11

Quadratic sequences

GCSE Maths quadratic sequences: constant second difference, nth term an² + bn + c — find a from half the second difference, then b and c from the first two terms.

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12

HCF and LCM

GCSE Maths HCF and LCM: prime factor trees, index form, the Venn method for two numbers, and HCF × LCM = product for a pair.

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13

Iteration and trial and improvement

GCSE Maths iteration: trial and improvement to find roots of equations, iterative formulas xₙ₊₁ = f(xₙ), and when a solution converges or diverges.

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14

Quadratic graphs

GCSE Maths quadratic graphs: parabola shape, roots, y-intercept, turning point from completing the square, and sketching y = ax² + bx + c.

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Keep going

More GCSE Maths
in the same style.

GCSE Maths revision that treats method as the mark scheme: reverse percentages, compound interest, quadratic formula, completing the square, SOHCAHTOA, sine and cosine rules, vectors, tree diagrams and histograms, with working shown line by line.

All Maths revision