作业帮若(3xy+2)+|7-x-y|=0,求代数式（5xy+10y）-[-5x-（4xy-2y+3x）]的值.
来源：学生作业帮助网 编辑：作业帮 时间：2024/04/29 10:48:40
![若(3xy+2)+|7-x-y|=0,求代数式（5xy+10y）-[-5x-（4xy-2y+3x）]的值.](/uploads/image/z/552562-34-2.jpg?t=%E8%8B%A5%283xy%2B2%29%2B%7C7-x-y%7C%3D0%2C%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F%EF%BC%885xy%2B10y%EF%BC%89-%5B-5x-%EF%BC%884xy-2y%2B3x%EF%BC%89%5D%E7%9A%84%E5%80%BC.)
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若(3xy+2)+|7-x-y|=0,求代数式（5xy+10y）-[-5x-（4xy-2y+3x）]的值.
若(3xy+2)+|7-x-y|=0,求代数式（5xy+10y）-[-5x-（4xy-2y+3x）]的值.
若(3xy+2)+|7-x-y|=0,求代数式（5xy+10y）-[-5x-（4xy-2y+3x）]的值.
(3xy+2)^2+|7-x-y|=0,则 3xy+2=0,7-x-y=0,即 x+y=7,xy= -2/3 (5xy+10y)-[-5x-(4xy-2y+3x)] =5xy+10y-(-5x-4xy+2y-3x) =5xy+10y+5x+4xy-2y+3x =9xy+8x+8y =9xy+8(x+y) = 9*(-2/3)+8*7 = -6+56 = 50