If lines x + 2ay + a = 0, x + 3by + b = 0 and x + 4cy + c = 0 are concurrent,then a,b,c, are in
A.P
G.P
H.P
None of these
If P (a,b) lies on 3x + 2y = 13 and point Q (b,a) lies on 4x - y = 5 then the equation of PQ is
x - y = 5
x + y = 5
x + y = -5
x - y = -5
The equation of line which passes through (1,-2) and cuts equal intercepts with coordinate axis is.
x + y = 1
x - y = 1
x + y + 1 = 0
x - y - 2 = 0
The equation of lines passing through (3,2) and perpendicular to y = x is.
x - y =1
If lines 2x + 3ay - 1 = 0 and 3x + 4y + 1 = 0 are mutually perpendicular , then a =
2
-1/2
1/2
1
If lines 3x - y =2,5x + ay = 3 and 2x + y = 3 are concurrent ,then a =
3
-1
-2
If lines 3y + 4x = 1 , y = x + 5 and 5y + bx = 3 are concurrent,then the value of b is.
6
0
The angle between lines y = (2 - √3) x + 5 and y = (2 + √3) x - 7 is.
30o
45o
-60o
90o
If lines 3x - 4y - 13 = 0,8x - 11y - 33 = 0 and 2x - 3y + λ = 0 are concurrent , λ =
7
-7
5
-5
Lines a1x + b1y + c1 = 0 and a2x + b2y + c2 = 0 will be mutually perpendicular if.
a1 b2 - b1 a2 = 0
a1 a2 + b1 b2 = 0
a12 b2 + b12 a2 = 0
a1 b1 + a2 b2 = 0