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–²¨®£m³‰ (2x y + 7y ) - (6x y + 5y ) = (2x y + 7y ) + [-(6x y + 5y )]
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= 2x y + 7y - 6x y - 5y
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= -4x y + 2y
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–²¨®£m³‰ (5x)(3x - 2y) = 15x - 10xy
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= 6x - 4x + 9x - 6
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–²¨®£m³‰ 4x - 8x = 4x 3 - 8x
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