点(x,y)到直线的距离公式为
d=|x-y+1|/根号(2)=1
|x-y+1|=根号2
x-y+1=根号2 ,x-y+1=-根号2
x-y+1-根号2=0,x-y+1+根号2=0
答案貌似有问题