Area of a circle (AQA GCSE Maths): Flashcards

$A = \pi r^2$

Always radius, never diameter

Divide diameter by 2

$\frac{1}{2} \times \pi \times r^2$

Exactly half

Can earn method marks even if final answer is wrong

Using diameter instead of radius

cm² or mm²

Divide by 2 to convert to radius

1 d.p., 3 s.f., nearest cm²/mm², or exact in terms of $\pi$