This key facts covers The Key Idea within Factorising for GCSE Mathematics. Revise Factorising in Algebra for GCSE Mathematics with 12 exam-style questions and 3 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 2 of 13 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
The Key Idea
Find the Highest Common Factor (HCF) of all terms
ab + ac = a(b + c)
1️⃣
Find the HCF of the numbers
2️⃣
Find the common letters (with lowest power)
3️⃣
Write HCF outside, divide each term inside
Practice questions for Factorising
Which is the correct factorisation of 6x + 15?
A student factorises x² + 5x + 4 as (x + 4)(x + 4). Explain why this is incorrect and give the correct factorisation.
Quick recall flashcards
Factorising Rule
Find the HCF of all terms (numbers AND letters), put outside bracket, divide each term for inside.
Factorising
Take out highest common factor: 6x + 9 = 3(2x + 3)