The lines ax + 2y + 1 = 0, bx + 3y +1 = 0 and cx + 4y +1 = 0 are concurrent, show that a,b,c are in A.P.

Show that the lines 2x + 3y - 8 = 0 , x - 5y + 9 = 0 and 3x + 4y - 11 = 0 are concurrent.

If the straight lines. ax + amy + 1 = 0, bx + (m + 1)by + 1=0 and cx + (m +2)cy + 1=0, m!=0 are concurrent then a,b.c are in: (A) A.P. only for m = 1 (B) A.P. for all m (C) G.P. for all m (D) H.P. for all m

If the lines a x+12 y+1=0,\ b x+13 y+1=0 and c x+14 y+1=0 are concurrent, then a , b , c are in a. H.P. b. G.P. c. A.P. d. none of these

If the lines ax+12y+1=0, bx+13y+1=0 and cx+14y+1=0 are concurrent, then a,b,c are in:

If the straight lines a x + m ay + 1 =0 b x + ( m +1) by + 1 =0 cx + (m+2) cy +1 =0, m ne0 are concurrent, then a, b, c are in :

If the lines x - 2y - 6 = 0 , 3x + y - 4 and lambda x +4y + lambda^(2) = 0 are concurrent , then

The lines ax + by + c = 0, where 3a + 2b + 4c= 0, are concurrent at the point

Show that the straight lines : x-y-1=0, 4x + 3y = 25 and 2x-3y + 1 = 0 are concurrent.

If the lines (a-b-c) x + 2ay + 2a = 0 , 2bx + ( b- c - a) y + 2b = 0 and (2c+1) x + 2cy + c - a - b = 0 are concurrent , then prove that either a+b+ c = 0 or (a+b+c)^(2) + 2a = 0

If the lines ax+by+c=0, bx+cy+a=0 and cx+ay+b=0 (a, b,c being distinct) are concurrent, then