Question

Find the value of k so that the pair of equations X + 2 Y is equal to 5 and 3 X + K Y + 15 is equal to zero has a unique solution

Answer 1

x+2y=5........1

3x+ky+15=0 .........2

eqn from 1

x=5-2y,

the value of x in put up eqn 2

3(5-2y)+ky+15=0

15-6y+ky+15=0

ky-6y=-30

y(k-6)=-30,

for a unique solution..

k does not is equal to 0

so k=-infinite to +infinite, for every k does not equal to 0......