Question

If the pair of linear equations 10x+ 5y- (k- 5)= 0 and 20x+ 10y-k=0 has infinitely many solutions, then the value of k is (a) 5 (b) 10 (c) 2 (d) 8

Answer 1

Answer:

option a c d

Step-by-step explanation:

k should not equal to 10 .

hence , k can be any value except 10

Answer 2

Answer:

10

Step-by-step explanation:

10x+5y-k+5=0....( 1 ep )

20x+10y-k=0.....( 2 ep )

2× 1 ep

20x+10y-2k=-10....( 3 ep )

20x+10y-k=0....( 4 ep )

Subtract (3 ep) and (4 ep)

20x-20x=0 , 10y-10y=0 , -2k-(-k)= -k

-10-0=-10

-k=-10

K=10

Hope it's correct