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Area Formulas

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Flat, 2D	Curved, 3D (Surface Areas)
square a2 rectangle ab parallelogram bh trapezoid h ____________________ 2 (b1 + b2) circle π r2 or π d 2 ______________________________ 4 ellipse π r1r2 triangle 1 ____________________ 2 bh	sphere 4π r 2 cylinder 2π rh + 2π r 2 cone π ra + π r 2