由②得,y²=(5-x)²/4③
将③代入①,得|X-1|+(5-x)²/4=3,
当x≥1时,x-1+(5-x)²/4=3,整理得x²-6x+9=0,即(x-3)²=0,
所以x=3,y=±1;
当x