JEE Mains Model Paper 1

R(x,y) lies on 9x + 7y + 4 = 0
⇒ R (a,

(4+9a)

7

), centroid of ΔPQR = (h, k)
h = (

2+4+a

3

) =

6+a

3

..... (1)
k =

5−11− 4+9a 7

3

=

−46−9a

21

..... (2)
From (1) & (2) elimination a, we get 3h - 6 =

−(21k−46)

9

⇒ 27h + 21k - 54 + 46 = 0 or locus is 9x + 7y - 8/3 = 0
This line is parallel to N