Loading...
Loading...
Straight-line graphs are tested at every tier and form the basis for understanding gradients, intercepts and real-world modelling. Students need to plot lines from equations, find gradients and interpret y = mx + c.
Students make these errors again and again. Knowing them in advance gives you a head start.
Confusing gradient (steepness) with y-intercept (where the line crosses the y-axis)
Miscalculating the gradient by getting rise and run the wrong way round
Plotting points inaccurately on the coordinate grid
Insights pulled from Cambridge IGCSE (0580) examiner reports — the exact mistakes candidates make every year.
You can ONLY cancel FACTORS (things multiplied), not terms added/subtracted. Factorise numerator and denominator first, then cancel matching brackets. Never cancel x² from x² − 25.
“Candidates who recognised that the numerator and denominator should be first factorised to create products were frequently successful. However, a common wrong approach was to merely cancel the x² in the first step with (x² − 25)/(x² − x − 20) = −25/(−x − 20) = 5/(x + 4), or similar, commonly seen.”
Source: CIE 0580 · November 2021 · Paper 4 · Q7a
In 'show that k = 8' questions, you must DERIVE 8, not assume it. Starting from 'k = 8' and working both ways is circular and scores zero. Work from the given info towards the target.
“This 'show that' question was often not attempted. Candidates who did attempt it often did not gain credit as they generally used the answer of k = 8 as part of their working. Candidates should be reminded that in any 'show that' question candidates must not use what they are asked to show as part of their answer.”
Source: CIE 0580 · November 2021 · Paper 3 · Q5
When raising a power to a power, MULTIPLY the exponents: (x³)³ = x⁹, not x⁶. But for coefficients like (4x³)³, the coefficient is raised: 4³ = 64, not 4 × 3 = 12.
“A small number incorrectly simplified the power by adding to give 6 rather than multiplying to give 9. Others correctly multiplied the powers but also multiplied the coefficient giving the incorrect answer of 12x⁹.”
Source: CIE 0580 · June 2024 · Paper 2 · Q21b
Based on 3of 510+ insights extracted from CIE 0580 examiner reports (2018–2024).
This topic is tested by the following exam boards. Our AI tutor covers each one with board-specific content.
Simultaneous equations require students to find values that satisfy two equations at the same time. Foundation students solve linear pairs, while higher-tier students tackle one linear and one quadratic equation together.
Inequalities extend equation-solving skills by introducing ranges of solutions rather than single values. Students must solve, represent on number lines, and at higher tier shade regions on graphs defined by multiple inequalities.
Quadratic graphs produce a characteristic U-shape (parabola) and are tested at both foundation and higher tier. Students must plot quadratics from tables, identify key features like turning points and roots, and use graphs to solve equations.
Algebra accounts for a large share of IGCSE maths marks. Here is exactly what examiners award marks for — and the specific presentation errors that cost students credit.
Exam PreparationGCSE marking is more systematic than most students realise. Understanding M marks, A marks, follow-through rules and QWC can recover marks you did not know you had.
Exam PreparationExaminer reports flag the same errors every sitting. These 10 mistakes cost GCSE maths students marks year after year — and every one of them is fixable with the right habit.
Take our free diagnostic quiz to find out exactly where you stand, then practise algebra with our AI tutor.