Home
Class 11
MATHS
I the lines a x+12 y+1=0,\ b x+13 y+1=0 ...

I 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

Text Solution

Verified by Experts

Since the given lines are concurrent ∴`[[a,12,1],[b,13,1],[c,14,1]]=0`
`=>[[a,12,1],[b-a,1,0],[c-b,1,0]]=0`
[Applying `R3→ R3−R2, R2→R2−R1]`
`=>b−a−c+b=0`
or` 2b=a+c=>a,b,c` are in`A.P`.
Promotional Banner

Topper's Solved these Questions

  • THE CIRCLE

    RD SHARMA|Exercise Solved Examples And Exercises|144 Videos
  • TRANSFORMATION FORMULAE

    RD SHARMA|Exercise Solved Examples And Exercises|145 Videos

Similar Questions

Explore conceptually related problems

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 lines ax+2y+1=0,bx+3y+1=0 and cx+4y+1=0 are concurrent,then a,b,c are in a.A.P.b.G.P.c.H.P. d.none of these

If the lines ax+2y+1=0,bx+3y+1=0 and cx+4y+1=0 are concurrent,then a,b,c are in A.P.( b) G.P.( c) H.P.(d) None of these

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: (1) A.P.(2) G.P.(3) H.P.(4) A.G.P.

If the lines x+a y+a=0,\ b x+y+b=0\ a n d\ c x+c y+1=0 are concurrent, then write the value of 2a b c-a b-b c-c adot

If x,y,z are in A.P. then : yz,zx,xy are in (a) A.P (b) G.P (c) H.P (d) no definite sequence

If a,b,c are in A.P.the (a)/(bc),(1)/(c),(2)/(b) will be in a. A.P b.G.P.c.H.P.d.none of these

If (b+c)/(a+d)= (bc)/(ad)=3 ((b-c)/(a-d)) then a,b,c,d are in (A) H.P. (B) G.P. (C) A.P. (D) none of these

If the lines ax+y+1=0,x+by+1=0 and x+y+c=0 are concurrent,prove that (1)/(1-a)+(1)/(1-b)+(1)/(1-c)=1

RD SHARMA-THE STRAIGHT LINES -Solved Examples And Exercises
  1. The point which divides the join of (1,2) and(3,4) externally in the ...

    Text Solution

    |

  2. A line passes through the point (2,2) and is perpendicular to the lin...

    Text Solution

    |

  3. I the lines a x+12 y+1=0,\ b x+13 y+1=0 and c x+14 y+1=0 are concurren...

    Text Solution

    |

  4. The number of real values of lambda for which the lines x-2y+3=0,\ lam...

    Text Solution

    |

  5. The equations of the sides A B ,\ B C\ a n d\ C A\ of\ triangleA B C\ ...

    Text Solution

    |

  6. If p1a n d\ p2 are the lengths of te perpendiculars from the origin...

    Text Solution

    |

  7. Area of the triangle formed by the points ((a+3)(a+4),\ a+3),\ ((a+2)(...

    Text Solution

    |

  8. If a+b+c=0 , then the family of lines 3a x+b y+2c=0 pass through fixed...

    Text Solution

    |

  9. The line segment joining the points (-3,-4), and (1,-2) is divided by ...

    Text Solution

    |

  10. The area of a triangle with vertices at (-4,-1), (1,2) and (4,-3) is ...

    Text Solution

    |

  11. The line segment joining the points (1,2) and (-2,1) is divided by the...

    Text Solution

    |

  12. If the point (5,2) bisects the intercept of a line between the axes, ...

    Text Solution

    |

  13. A\ (6,3),\ B(-3,5),\ C(4,-2)\ a n d\ D(x ,3x) are four points. If "Del...

    Text Solution

    |

  14. If p be the length of theperpendicular from the origin on the line x//...

    Text Solution

    |

  15. The equation of the line passing through (1,5) and perpendicular to th...

    Text Solution

    |

  16. The figure formed by the lines a x+-y+-c=0 is a. a rectangle b. a squa...

    Text Solution

    |

  17. Two vertices of triangle are (-2,-1) and (3,2) and third vertex lies o...

    Text Solution

    |

  18. (i) Find the gradient of a straight line which is passes through the p...

    Text Solution

    |

  19. The angle between the lines 5x+3y-7=0\ a n d\ 15 x+9y+14=0 is ^0 d. 30...

    Text Solution

    |

  20. Distance between the lines 5x+3y-7=0\ a n d\ 15 x+9y+14=0 is (35)/(sq...

    Text Solution

    |