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AQASpec G16-G17Foundation & Higher~25 min

Area & Perimeter

Mathematics · Topic revision workspace

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Read the notes, score 80% and know 75% of the cards.

Topic overview

What you need to know

Area & Perimeter is a key part of GCSE Mathematics. Build fluency with the method, then apply it to unfamiliar and multi-step problems. The total distance around the outside of a 2D shape. Add up all the side lengths. Area = length × width. Area = ½ × base × height (perpendicular height, not slant height).

Exam tip

Write every stage of your method. Method marks can still be earned when the final answer is wrong.

Revision notes

Core ideas

Secure these ideas first. Say each definition in your own words, then connect it to the topic overview.

  • Perimeter: The total distance around the outside of a 2D shape. Add up all the side lengths.
  • Area of a Rectangle: Area = length × width.
  • Area of a Triangle: Area = ½ × base × height (perpendicular height, not slant height).
  • Area of a Parallelogram: Area = base × perpendicular height.

Revision notes

Apply it in the exam

The exam will rarely ask for an isolated definition. Practise selecting the right idea and using it as part of a complete explanation or method.

  • Area of a Trapezium: Area = ½ × (a + b) × h, where a and b are the parallel sides and h is the perpendicular height.
  • Area of a Circle: Area = πr², where r is the radius.
  • Circumference of a Circle: Circumference = 2πr = πd, where r is the radius and d is the diameter.
  • Area of a Sector: Area = (θ/360) × πr², where θ is the angle of the sector.

Core knowledge

Key facts for Area & Perimeter

1

Perimeter

The total distance around the outside of a 2D shape. Add up all the side lengths.

2

Area of a Rectangle

Area = length × width.

3

Area of a Triangle

Area = ½ × base × height (perpendicular height, not slant height).

4

Area of a Parallelogram

Area = base × perpendicular height.

5

Area of a Trapezium

Area = ½ × (a + b) × h, where a and b are the parallel sides and h is the perpendicular height.

6

Area of a Circle

Area = πr², where r is the radius.

7

Circumference of a Circle

Circumference = 2πr = πd, where r is the radius and d is the diameter.

8

Area of a Sector

Area = (θ/360) × πr², where θ is the angle of the sector.

Active recall

Close the notes and answer these

  1. 1.Without looking, explain perimeter and give one example or consequence.
  2. 2.Without looking, explain area of a rectangle and give one example or consequence.
  3. 3.Without looking, explain area of a triangle and give one example or consequence.
  4. 4.Without looking, explain area of a parallelogram and give one example or consequence.

Content reviewed 23 July 2026 against the current linked specification.

Finished learning?

Mark the notes complete, then test what you can recall.

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