Area Practice
Practise finding the area of rectangles, squares and triangles — the amount of surface a shape covers.
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How to find area
Area measures how much flat space a shape covers, counted in square units. Each shape has its own simple formula, but they all come from the same idea of covering the shape with unit squares.
- Rectangle: length × width.
- Square: side × side.
- Triangle: ½ × base × height (it’s half a rectangle).
Worked examples
Tips & common mistakes
Area is always in square units — that’s the giveaway that you should be multiplying two lengths. The triangle catches people out: it’s half a rectangle, so don’t forget the ½. Type your answer as a number.
- Adding the sides instead of multiplying — that gives perimeter, not area.
- Forgetting the ½ for a triangle.
- Using the slanted side of a triangle instead of the height (the height is straight up from the base).
Frequently asked questions
How do you find the area of a rectangle?
Multiply length by width. A 5 by 3 rectangle has an area of 15 square units.
What is the formula for the area of a triangle?
Half the base times the height: ½ × b × h. A triangle is half of a rectangle with the same base and height.
What’s the difference between area and perimeter?
Area is the space inside a shape (square units); perimeter is the distance around its edge (just units).
Why is area measured in square units?
Because you’re counting how many unit squares fit inside, which comes from multiplying two lengths.
What grade is area?
Area of rectangles starts in grade 3; squares and triangles follow through grade 6.