x,y互为相反数
x+y=0
y=-x
(2x-3)^2-(2y+1)^2=48
(2x-3)^2-(1-2x)^2=48
(2x-3+1-2x)(2x-3-1+2x)=48
-2(4x-4)=48
4x-4=-24
4x=-20
x=-5
x=-5,y=5