Question

find the value of k for which the lines (k+1)x +13ky + 15=0 and 5x+ky+15=0 are coincident.
Plzz help

Answer 1

Hi ,

Compare ( k + 1 )x + 13ky + 15 = 0 ,

5x + ky+ 15 = 0 with a1 x +b1 y + c1 = 0

and a2 x + b2 y + c2 = 0 we get,

a1 = k + 1 , b1 = 13k. c1 = 15 ,

a2 = 5 , b2 = k , c2 = 15 ;

a1/a2 = b1/b2 = c1/c2

[ Since lines are coincident each

other ]

( k + 1 ) / 5 = 13k/k

( k + 1 ) / 5 = 13

k + 1 = 13 × 5

k + 1 = 65

k = 65 - 1

k = 64

I hope this helps you.

: )