To find the area you multiply the length of the area by the width, to find the perimeter you add together the length of all the sides of the area.
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1. Start with a parallelogram. A parallelogram may be a square, a rectangle or a rhombus. In a parallelogram, the sides of the foursided shape must have two sets of parallel lines.
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1 Check to see if all the sides are the same length. A polygon with all sides the same length and all angles the same measure is called a regular polygon. Squares and equilateral
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Perimeter = The sum of the lengths of all sides of a shape
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