y=(x-1)² y=-x²+1 y=-x²-1
y=x+1 y+1=0 y=1 xy=1
xy=-1 x+y=2 х²+y²=25 xy=1
|x|-y=0 |y|=x |x|+2=y у=|х|
(x-1)²+(y-1)²=1 xy=5 х²+y²=1 х²=y