COMEDK Exam 2017 Solved Paper

Let the coordinates of a point P changes from (x,y) to (x′,y′) in new coordinates axes where origin has the coordinates h=1
k=1
Then, ‌‌x=x′+1,y=y′+1.
Substituting these values in the given equation of straight line
‌(x′+1)(y′+1)−(x′+1)−(y′+1)+1=0
⇒x′y′+x′+y′+1−x′−1−y′−1+1=0
⇒x′y′=0
Therefore, the equation of straight line in the new system is xy=0