Question

If 3a + 2b + 6c = 0 the family of straight lines ax + by + c = 0 passes through a fixed point. Find the coordinates of fixed point.

Solution

Correct option is

 

Given,  

        3a + 2b + 6c = 0    

       

and family of straight lines is  

        ax + by + c = 0                   … (ii) 

Substituting (i) from (ii) then 

       

which is equation of a line passing through the point of intersection of the lines.    

          

∴ The coordinates of fixed point are, 

       .

SIMILAR QUESTIONS

Q1

 

Find the general equation of the line which is parallel to

3x – 4y + 5 = 0. Also find such line through the point (–1, 2).

Q2

Find the general equation of the line which perpendicular to x + y + 4 = 0. Also find such line through the point (1, 2).   

Q3

Find the sum of the abscissas of all the points on the line x + y = 4 that lie at a unit distance from the line 4x + 3y – 10 = 0.

Q4

If p and p’ are the length of the perpendiculars from the origin to the straight line whose equations are , then find the value of 4p2 + p2.

Q5

 

Find the distance between the lines 5x – 12y + 2 = 0 and

 5x – 12y – 3 = 0.

Q6

Find the equations of the line parallel to 5x – 12y + 26 = 0 and at a distance of 4 units from it.

Q7

If the lines ax + y + 1 = 0, x + by + 1 = 0 and x + y + c = 0 (ab and cbeing distinct and difference from 1) are concurrent, then find the value of

Q8

Find the equation of the straight line passing through the point (2, 1) and through the point of intersecction of the lines x + 2y = 3 and 2x – 3y = 4.

Q9

The family of lines x(a + 2b) + y(+ 3b) = b passes through the point for all values of a and b. Find the point.

Q10

 

Find the equation of the line passing through the point of intersection of the lines

          x + 5y + 7 = 0, 3x + 2y – 5 = 0 and   

1. parallel to the line 7x + 2y – 5 = 0

2. perpendicular to the line 7x + 2y – 5 = 0