There are two main ways to find the perimeter of a rectangle:
Method 1: Adding all side lengths
A rectangle has four sides: two long sides with the same length (often called length) and two shorter sides with the same length (often called width).
Here's the formula:
Perimeter = Length (long side) + Width (short side) + Length + Width
Why it works: By adding the length once, width once, another length, and another width, you essentially add up the lengths of all four sides.
Example:
Imagine a rectangle with a length of 5 meters (long side) and a width of 3 meters (short side).
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Perimeter = 5 meters + 3 meters + 5 meters + 3 meters
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Perimeter = 16 meters
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:
Here's the formula:
Perimeter = 2 (Length + Width)
Why it works: The number 2 represents that you're adding the length and width twice since there are two sides of each length in a rectangle.
Using the formula is generally more efficient for rectangles specifically as it avoids repetitive addition.
Example (using the same rectangle from before):
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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