If I,m, n are in A.P then the lines represented by `lx + my+n=0` are concurrent at the point

If a,b,c are in A.P then the lines represented by ax+by+c=0 are concurrent at the point

If l, m, n are in AP, then the line lx+my+n=0 will always pass through the point

If 9l^(2)+16m^(2)-n^(2)-24lm=0 then the family of straight lines lx+my+n=0 are concurrent.The points of concurrency are

If lx + my + n = 0 , where l, m, n are variables, is the equation of a variable line and l, m, n are connected by the relation al+bm+cn=0 where a, b, c are constants. Show that the line passes through a fixed point.

If the lines lx + my + n = 0, mx + ny + l = 0 and nx + ly + m = 0 are concurrent then

The lines lx+my+n=0,mx+ny+l=0 and nx+ly+m=0 are concurrent if (where l!=m!=n)

Straight lines are drawn by joining m points on a straight line of n points on another line. Then excluding the given points, the number of point of intersections of the lines drawn is (no tow lines drawn are parallel and no these lines are concurrent). a. 4m n(m-1)(n-1) b. 1/2m n(m-1)(n-1) c. 1/2m^2n^2 d. 1/4m^2n^2