Question

For what value of 'k' does the pair of linear equations 2x - y - 3 = 0 and 2kx + 7y - 5 = 0 have a unique solution x = 1 & y = - 1? A) 3 B) 4 C) 6 D) - 6​

Answer 1

Answer:

6

Step-by-step explanation:

Given:

2x-y-3=0

2kx+7y-5=0

x=1 y=-1

substitute.....

2x1-(-1)-3=0

2kx1+7x(-1)-5=0

=> 2+1-3=0 ; 2k-7-5=0

=> 3-3=0 ; 2k-12=0

=> 0 ; 2k=12

=> k=12/2

=> k=6

Hope this helps you to understand easier.....