Home
Class 11
MATHS
If the image of point P(2, 3) in a line ...

If the image of point `P(2, 3)` in a line `L` is `Q (4,5)` then, the image of point `R (0,0)` in the same line is:

A

(3,2)

B

(-2,3)

C

(-3,-2)

D

(3,-2)

Text Solution

AI Generated Solution

The correct Answer is:
To find the image of point \( R(0,0) \) in the same line \( L \) where the image of point \( P(2,3) \) is \( Q(4,5) \), we can follow these steps: ### Step 1: Find the Midpoint of Points P and Q The midpoint \( M \) of points \( P(2,3) \) and \( Q(4,5) \) can be calculated using the midpoint formula: \[ M = \left( \frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2} \right) \] Substituting the coordinates of \( P \) and \( Q \): \[ M = \left( \frac{2 + 4}{2}, \frac{3 + 5}{2} \right) = \left( \frac{6}{2}, \frac{8}{2} \right) = (3, 4) \] ### Step 2: Determine the Slope of Line PQ The slope \( m_{PQ} \) of line \( PQ \) can be calculated using the formula: \[ m_{PQ} = \frac{y_2 - y_1}{x_2 - x_1} \] Substituting the coordinates of \( P \) and \( Q \): \[ m_{PQ} = \frac{5 - 3}{4 - 2} = \frac{2}{2} = 1 \] ### Step 3: Find the Slope of Line L Since line \( L \) is perpendicular to line \( PQ \), we can find the slope of line \( L \) using the relationship: \[ m_{PQ} \cdot m_{L} = -1 \] Thus, \[ 1 \cdot m_{L} = -1 \implies m_{L} = -1 \] ### Step 4: Write the Equation of Line L Using the point-slope form of the line equation: \[ y - y_1 = m(x - x_1) \] where \( (x_1, y_1) = (3, 4) \) and \( m = -1 \): \[ y - 4 = -1(x - 3) \] Simplifying this: \[ y - 4 = -x + 3 \implies x + y - 7 = 0 \] ### Step 5: Find the Image of Point R(0,0) Let the image of point \( R(0,0) \) be \( S(p,q) \). The midpoint \( N \) of \( R(0,0) \) and \( S(p,q) \) must lie on line \( L \): \[ N = \left( \frac{0 + p}{2}, \frac{0 + q}{2} \right) \] Substituting into the line equation: \[ \frac{p}{2} + \frac{q}{2} - 7 = 0 \implies p + q = 14 \quad \text{(1)} \] ### Step 6: Use the Slope Condition The slope of line \( RS \) is given by: \[ \text{slope of } RS = \frac{q - 0}{p - 0} = \frac{q}{p} \] Since line \( RS \) is perpendicular to line \( L \) (which has a slope of -1): \[ \frac{q}{p} \cdot (-1) = -1 \implies q = p \quad \text{(2)} \] ### Step 7: Solve the System of Equations From equations (1) and (2): 1. \( p + q = 14 \) 2. \( q = p \) Substituting \( q = p \) into equation (1): \[ p + p = 14 \implies 2p = 14 \implies p = 7 \] Thus, \( q = 7 \). ### Conclusion The image of point \( R(0,0) \) in line \( L \) is: \[ S(7,7) \]

To find the image of point \( R(0,0) \) in the same line \( L \) where the image of point \( P(2,3) \) is \( Q(4,5) \), we can follow these steps: ### Step 1: Find the Midpoint of Points P and Q The midpoint \( M \) of points \( P(2,3) \) and \( Q(4,5) \) can be calculated using the midpoint formula: \[ M = \left( \frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2} \right) \] Substituting the coordinates of \( P \) and \( Q \): ...
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • STRAIGHT LINES

    OBJECTIVE RD SHARMA ENGLISH|Exercise ILLUSTRATION 18|1 Videos
  • STRAIGHT LINES

    OBJECTIVE RD SHARMA ENGLISH|Exercise Section I - Solved Mcqs|64 Videos
  • SETS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|30 Videos

Similar Questions

Explore conceptually related problems

If the image of the point (-4, 3, -5) in XZ-plane is Q then the coordinates of Q is

The image of the point (1, 3) in the line x + y-6 = 0 is

Knowledge Check

  • If the image of the point (2,1) in a line is (4,3) then the equation of line is (i) x+y+5=0 (ii) x-y+5=0 (iii) x+y-5=0 (iv) x-y-5=0

    A
    `x+y+5=0`
    B
    `x-y+5=0`
    C
    `x+y-5=0`
    D
    `x-y-5=0`
  • If the image of the point (-3,k) in the line 2x+y-2=0 is the point (1,5) then the value of k is (i) 2 (ii) 3 (iii) -3 (iv) 1

    A
    2
    B
    3
    C
    `-3`
    D
    1
  • Similar Questions

    Explore conceptually related problems

    The image of the point (1, 3) in the line x + y-6 = 0 is

    Find the image of the point (4,-13) in the line 5x+y+6=0.

    Find the image of point P(3,-1) in the point A (-5, 2).

    The image of the point (-1,3) by the line x - y = 0 , is

    Find the image of the point (1, 2) in the line x - 3y + 4 = 0 .

    Find the image of the point (2,3,-1) in the point (3,0,4).