Perimeter of a Square
Total length around a square.
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Example
a = 5 → P = 20
How it works
A square has four sides of equal length, so the total distance around it is found by adding the same side length four times. That is why the perimeter formula is P = 4a: it combines all four equal sides into one expression. This tells you the boundary length of the square, not the space inside it.
When to use it
Use this formula whenever you know the length of one side of a square and need the distance around the outside. It appears in geometry, construction, fencing, tiling layouts, and any problem involving square borders or frames.
Worked example, step by step
Suppose the side length is a = 8 cm. P = 4a P = 4 × 8 P = 32 cm So, the perimeter of the square is 32 cm.
Common mistakes to avoid
- Using the area formula instead of the perimeter formula
- Forgetting that a square has 4 equal sides
- Leaving the answer without units
Did You Know?
A square encloses the most area of any rectangle with a given perimeter.
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