解方程组 (x+y)^2-3(x+y)=54 (x-y)^2-5(x-y)=14
问题描述：
解方程组 (x+y)^2-3(x+y)=54 (x-y)^2-5(x-y)=14
答
(x+y)^2-3(x+y)=54 (1)(x-y)^2-5(x-y)=14 (2)由(1)得(x+y-9)(x+y+6)=0∴x+y=9 x+y=-6由(2)得(x-y-7)(x-y+2)=0∴x-y=7 x-y=-2∴可组成四个方程组x+y=9 x+y=9 x+y=-6 x+y=-6x-y=7 x-y=-2 x-y=7 x-y=-2∴x=8 x=7/2 x=1/...