Factorising to solve x² + bx + c = 0

Sample Factorising to solve x² + bx + c = 0 questions

A few of the 50 questions, from easier to harder. Choose your exam board and tier to practise them, with every answer marked.

1. Question 12 marksGrade 4-5
   Solve $x^2 + 4x + 3 = 0$ by factorising.
   Show the worked solution

   Factorise: find two numbers that multiply to give 3 and add to give 4 - these are 3 and 1.

   $x^2 + 4x + 3 = (x + 3)(x + 1) = 0$

What are the common mistakes in Factorising to solve x² + bx + c = 0?

When a pupil makes one of these on Revision Workshop, the marking engine names the mistake and explains it, instead of just marking the answer wrong.

• Gives only one root of a quadratic equation instead of both

  Found one correct solution ($x = 3$) but a quadratic equation usually has two solutions - the other factor also gives a valid root ($x = -2$)

• Rearranges only part of the equation, leaving it not fully solved for the required variable

  Moved the constant term across but forgot the $x$

Quick answers about Factorising to solve x² + bx + c = 0

How many Factorising to solve x² + bx + c = 0 practice questions are there?

There are 50 self-marking GCSE and IGCSE Maths questions on Factorising to solve x² + bx + c = 0, written for AQA, Pearson, OCR, Pearson International GCSE Maths A (4MA1), Cambridge IGCSE Mathematics (0580), Cambridge IGCSE (9-1) Mathematics (0980) across Foundation and Higher and Extended tier. Each one is marked instantly and has a full worked solution.

Do I need an account to practise Factorising to solve x² + bx + c = 0?

No. You can start practising Factorising to solve x² + bx + c = 0 straight away without an account. A free account keeps your results across sessions, so you can see your progress on this topic over time.