1) а² - 49 = (а - 7)(а + 7)
2) (x - 5)(x + 6) = x² + 6x - 5x - 30 = x² + x - 30
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1) а² - 49 = (а - 7)(а + 7)
2) (x - 5)(x + 6) = x² + 6x - 5x - 30 = x² + x - 30
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