Question

26. What is the value of k, if the value of Dy for the equations
3x +y=1 and 2x – ky=3 is 7?​

Answer 1

Step-by-step explanation:

2x−ky+3=0

3x+2y−1=0

These equations are of the form

a

1

x+b

1

y+c

1

=0,a

2

x+b

2

y+c

2

=0

where a

1

=2,b

1

=−k,c

1

=3, and a

2

=3,b

2

=2,c

2

=−1

Now, for the given pair to have no solution,

a

2

a

1

=

b

2

b

1



=

c

2

c

1

3

2

=

2

−k



=

−1

3

3

2

=−

2

k

and

2

−k



=

−1

3

k=−

3

4

and k



=6

Therefore, k=−

3

4