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Calculate the perimeter of the square 𝐴𝐵𝐶𝐷.
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The perimeter is the distance around a two-dimensional shape.
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We find it by adding all the side lengths together.
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What do we know about a square?
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In a square, all side lengths are equal.
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To find the perimeter of a square, we multiply four times one of the side lengths.
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That is the same thing as saying the perimeter equals side plus side plus side plus side.
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So instead of doing repeated addition four times, we can multiply our side length by four.
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In this case, the side length is 37 centimeters and we need to multiply that by four.
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Starting all the way on the right, we say four times seven equals 28.
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We write our eight down and carry our two.
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Moving on to the tens place, we say four times three equals 12 plus the two that we carried over equals 14.
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So we bring down that 14.
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37 times four equals 148.
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But make sure we don’t forget the units.
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They’re a very important part of calculating the perimeter.
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We can bring those units down to tell us that the perimeter of this square is 148 centimeters.