The perimeter of any closed shape is the total length of all its sides added together. Here's how to find the perimeter of a rectangle:
Method 1: Adding all side lengths
Since a rectangle has four sides, you can simply find the perimeter by adding the lengths of all four sides.
Formula: Perimeter = Length (long side) + Width (short side) + Length + Width
Here's why it works:
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Rectangles have two long sides with the same length (often called length) and two shorter sides with the same length (often called width).
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By adding the length once, width once, another length, and another width, you essentially add up the lengths of all four sides.
**Method 2: Using a simpler formula (**more efficient for rectangles specifically)
Knowing that rectangles have two equal lengths and two equal widths, we can express the perimeter in a shorter formula:
Formula: Perimeter = 2 (Length + Width)
Here's why it works:
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The number 2 represents that you're adding the length and width twice since there are two sides of each length in a rectangle.
Example:
Imagine a rectangle with a length of 5 meters (long side) and a width of 3 meters (short side).
Method 1:
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Perimeter = 5 meters + 3 meters + 5 meters + 3 meters
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Perimeter = 16 meters
Method 2:
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Perimeter = 2 (5 meters + 3 meters)
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Perimeter = 2 x 8 meters
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Perimeter = 16 meters
Both methods give you the same answer: the perimeter of the rectangle is 16 meters.
Using the formula is generally more efficient for rectangles specifically as it avoids repetitive addition.