Overview
Calculate the area of rectangles, squares, triangles and circles using common formulas.
Objective
Use the correct measurements, units and method to produce an accurate, clearly labelled result.
What You Need
- Shape dimensions
- Correct area formula
- Calculator if needed
Before You Start
Write down the value or dimensions you have, including their units. Decide exactly what unit or result you need before calculating. Keeping the units visible makes errors much easier to spot.
How to Do It
- Identify the shape.
- Measure or note the required dimensions.
- Use the correct area formula.
- Calculate carefully.
- Write the answer in square units.
Worked Example
A rectangle 5 m by 3 m has area 5 × 3 = 15 m².
Useful Tips
- Draw and label the dimensions.
- Check that all measurements use the same unit.
- Area answers use squared units.
Common Mistakes
- Using a perimeter formula.
- Forgetting to halve base × height for a triangle.
- Writing metres instead of square metres.
Important Notes
Conversion factors and measurement standards can vary by country or context. When accuracy matters, confirm the standard being used and keep enough decimal places until the final answer.
FAQ
When should I round the answer?
Keep the full value during the calculation and round at the end to a level of precision suitable for the task.
Why should I always write the units?
The unit tells you what the number represents and helps reveal mistakes when converting or calculating.