Since a = 3 and b = 12 is the solution of required equations. So we have to find the set of any two equations which satisfy this point.
Consider 4a – b = 0 and 3a – b + 3 = 0 set of lines which are passing through (3, 12).
We know, infinite lines can be pass through a point. So, there are infinite lines passing through (3, 12).
