9×(1.2的方)-16×(1.4的方) 因式分解...

问题描述:

9×(1.2的方)-16×(1.4的方) 因式分解
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9×1.2^2 - 16×1.4^2 = 3.6^2 - 5.6^2 = (3.6 - 5.6)×(3.6+5.6)
= (-2)×9.2 = -18.4