Q.

For what values of k will the following pair of linear equations have infinitely many solutions  kx + 3y – (k – 3) = 0 and 12x + ky – k = 0


Ans.

(6)

Comparing with a1x+b1y=c1 and a2x+b2y=c2

a1=k, a2=12, b1=3, b2-k, c1=k-3, c2-k

For infinite solutions, a1a2=b1b2=c1c2

 k12=3k=k-3kk12=3kk2=36k=6