The point P(a,b) lies on the straight line `3x+2y=13` and the point `Q(b,a)` lies on the straight line `4x-y=5` , then the equation of the line PQ is

Options

A. x-y=5
B. x+y=5
C. x+y=-5
D. x-y=-5

Answer

B

Explanation

Since point P(a,b) lies on 3x +2y =13
3a + 2b =13
and point Q(b,a) lies on 4x -y=5
4b -a=5
On solving Eqs. (i) and (ii) we get a=3, b=2
Therefore, the coordinates of P and Q are (3,2) and (2,3) respectively.
Now , equation of PQ is
` y-2 (3-2)/(2-3) (x-3) Rightarrow x+y=5` ,