Area = width × height. Diagonal = √(width² + height²).
Calculate a rectangle's area, perimeter, diagonal and the diagonal's angle from its length and width — a square or golden-ratio pair of sides is called out when it occurs — with the formulas shown, free online, no signup needed.
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Calculate a rectangle's area, perimeter, diagonal and the diagonal's angle from its length and width — a square or golden-ratio pair of sides is called out when it occurs — with the formulas shown, free online, no signup needed.
Width 8 and height 5 give area 40, perimeter 26 and a diagonal of about 9.434 meeting the width at about 32.01°. Equal sides are called out as a square, and a pair in the golden proportion (about 1.618 to 1) is flagged as a golden rectangle.
Area = width × height. Diagonal = √(width² + height²).
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