Question:
Find what the given equation becomes when the origin is shifted to the point (1, 1).
$x y-y^{2}-x+y=0$
Solution:
Let the new origin be (h, k) = (1, 1)
Then, the transformation formula become:
$x=X+1$ and $y=Y+1$
Substituting the value of x and y in the given equation, we get
$x y-y^{2}-x+y=0$
Thus
$(X+1)(Y+1)-(Y+1)^{2}-(X+1)+(Y+1)=0$
$\Rightarrow X Y+X+Y+1-\left(Y^{2}+1+2 Y\right)-X-1+Y+1=0$
$\Rightarrow X Y+X+Y+1-Y^{2}-1-2 Y-X+Y=0$
$\Rightarrow X Y-Y^{2}=0$
Hence, the transformed equation is $X Y-Y^{2}=0$