已知(x-2y)2+|5x-7y-2|=0,求x、y.
题型:解答题难度:一般来源:不详
已知(x-2y)2+|5x-7y-2|=0,求x、y. |
答案
∵(x-2y)2和|5x-7y-2|都是非负数,且(x-2y)2+|5x-7y-2|=0, ∴ | x-2y=0----(1) | 5x-7y-2=0--(2) |
| | , 解得. |
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