Question

If 2 X + 3 y + 5 = 0,Kx+ 6y + 7 = 20 are parallel then the value of k is

Answer 1

let 2x + 3y + 5 = 0 (equation 1)
kx + 6y + 7 = 20 ( equation 2)
2x + 3y + 5 = 0
5xy = -5
xy = -5/5
xy = -1
kx + 6y + 7 =20
k x -1 + 6 x -1 + 7 = 20
-k + -6 + 7 =20
-k = 20 - 7 + 6
-k = 13 + 6
-k = 19

Answer 2

Given two equations -

2x + 3y + 5 = 0

kx + 6y + 7 = 20 ______( 1 )

On further solving ( 1 )

kx + 6y + 7 - 20 = 0

kx + 6y - 13 = 0

a1 = 2, a2 = k, b1 = 3, b2 = 6, c1 = 7, c2 = - 13

Condition for parallel lines -

a1 / a2 = b1 / b2

Putting values

2 / k = 3 / 6

2 / k = 1 / 2

k = 2 × 2

k = 4

^^'