Factorise the quadratic expression $x^2-16x+64$

Step-by-step solution

1. Recognise that $-16x$ is twice $-8x$ and $64$ is $8^2$.
2. Write the expression as $(x-8)(x-8)$.
3. Confirm by expanding: $(x-8{)}^2=x^2-16x+64$.
4. Thus the factorised form is $(x-8{)}^2$.

Concept tested: Factorising perfect square trinomials

Published 16 October 2026 · How this solution was prepared and checked