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已知﹣x+3y=5,求5(x-3y)²-8(x-3y)-5的值.急拜托拜托
人气:349 ℃ 时间:2020-06-19 13:01:36
解答
﹣x+3y=5
x-3y=-5
5(x-3y)²-8(x-3y)-5
=5x(-5)²-8x(-5)-5
=125+40-5
=160
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