22.已知x+4y=-1,xy=5,求(6xy+7y)+[8x-(5xy-y+6x)]的值.

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/04 07:52:47
22.已知x+4y=-1,xy=5,求(6xy+7y)+[8x-(5xy-y+6x)]的值.

22.已知x+4y=-1,xy=5,求(6xy+7y)+[8x-(5xy-y+6x)]的值.
22.已知x+4y=-1,xy=5,求(6xy+7y)+[8x-(5xy-y+6x)]的值.

22.已知x+4y=-1,xy=5,求(6xy+7y)+[8x-(5xy-y+6x)]的值.
原式=6xy+7y+8x-5xy+y-6x=xy+8y+2x=xy+2(x+4y)=5-2=3

原式=6xy+7y+8x-5xy+y-6x
=xy+8y+2x
=xy+2(x+4y)
=5-2
=3