作业帮已知：|x+4y+1|+(xy-5)²=0 求代数式﹙6xy+7y﹚﹢[8x﹣﹙5xy-y+6x﹚]的值
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![已知：|x+4y+1|+(xy-5)²=0 求代数式﹙6xy+7y﹚﹢[8x﹣﹙5xy-y+6x﹚]的值](/uploads/image/z/1972852-52-2.jpg?t=%E5%B7%B2%E7%9F%A5%EF%BC%9A%7Cx%2B4y%2B1%7C%2B%28xy-5%29%26%23178%3B%3D0+%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F%EF%B9%996xy%2B7y%EF%B9%9A%EF%B9%A2%5B8x%EF%B9%A3%EF%B9%995xy-y%2B6x%EF%B9%9A%5D%E7%9A%84%E5%80%BC)
已知：|x+4y+1|+(xy-5)²=0 求代数式﹙6xy+7y﹚﹢[8x﹣﹙5xy-y+6x﹚]的值
已知：|x+4y+1|+(xy-5)²=0 求代数式﹙6xy+7y﹚﹢[8x﹣﹙5xy-y+6x﹚]的值
已知：|x+4y+1|+(xy-5)²=0 求代数式﹙6xy+7y﹚﹢[8x﹣﹙5xy-y+6x﹚]的值
∵：|x+4y+1|+(xy-5)²=0
∴x+4y+1=0
xy-5=0
∴x+4y=-1
xy=5
﹙6xy+7y﹚﹢[8x﹣﹙5xy-y+6x﹚]
=6xy+7y+8x-5xy+y-6x
=xy+2(x+4y)
=5-2
=3
|x+4y+1|+(xy-5)²=0，所以x+4y=-1，xy=5
﹙6xy+7y﹚﹢[8x﹣﹙5xy-y+6x﹚]=xy+2x+8y=5-2=3