A straight line through a fixed point (2,3) intersects the coordinate axes at distinct points P and Q . If O is the origin and the rectangle OPRQ is completed, then the locus of R is :
(A)3x+2y=6xy
(B)3x+2y=6
(C)2x+3y=xy
(D)3x+2y=xy✓ Correct
Answer: (D)
Solution
If R=(a,b) completes the rectangle OPRQ with O at the origin, then P=(a,0) and Q=(0,b), so the line PQ is ax+by=1. It passes through the fixed point (2,3), giving a2+b3=1. Replacing a,b by x,y for the locus of R and clearing denominators, 2y+3x=xy, that is 3x+2y=xy.
JEE Main · 2018 · 08 Apr 2018 · Offline · Single correct option