If the lines `2x-ay+1=0,3x-by+1=0,4x-cy+1=0` are concurrent,then `a,b,c` are in `

If the lines 2x - ay + 1 = 0, 3x – by + 1 = 0, 4x-cy+1 =0 concurrent, then a, b, c are in (A) A.P. (B) G.P. (C) H.P. (D) A.G.P

If the lines x+2ay+a=0,x+3by+b=0 and x+4cy+c=0 are concurrent then a,b,c are in

If the lines x-y-1=0, 4x+3y=k and 2x-3y+1=0 are concurrent, then k is

If the lines 3x+2y-5=0,2x-5y+3=0,5x+by+c=0 are concurrent then b+c=

If the lines ax+by+c=0,bx+cy+a=0 and cx+ay+b=0 be concurrent,then: