Square (Geometry)
(Jump to Area of a Square or Perimeter of a Square)
A Square is a flat shape with 4 equal sides and every angle is a right angle (90°)
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 means "right angle" |
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 show equal sides |
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All sides are equal in length |
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Each internal angle is 90° |
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Opposite sides are parallel (so it is a Parallelogram). |
Play with a square:
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A square also fits the definition of a rectangle (all angles are 90°), and a rhombus (all sides are equal length).
Area of a Square
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The Area is the side length squared: Area = a2 = a × a |
Example: A square has a side length of 6 m, what is its Area?
Area = 6 m × 6 m = 36 m2
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The Area is also half of the diagonal squared:
Area = d2/2 |
Perimeter of a Square
The Perimeter is the distance around the edge.
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The Perimeter is 4 times the side length: Perimeter = 4a |
Example: A square has a side length of 12 cm, what is its Perimeter?
Perimeter = 4 × 12 cm = 48 cm
Diagonals of a Square
A square has two diagonals, they are equal in length and intersect in the middle.
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The Diagonal is the side length times the square root of 2: Diagonal "d" = a × √2 |
Example: A square has a side length of 5 m, what is the length of a diagonal?
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Diagonal Length = a × √2 = 5 × 1.41421... = 7.071 m (to 3 decimals) |