Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Straight Lines and Pair of Straight Lines question

2014 · Shift 0 · Q38
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /JEE Main
  3. /Mathematics
  4. /Straight Lines and Pair of Straight Lines
  5. /2014 · Shift 0 · Q38

Straight Lines and Pair of Straight Lines question

2014 · Shift 0 · Q38

JEE MainMathematicsStraight Lines and Pair of Straight LinesMCQ+4 / −1
Let PSPSPS be the median of the triangle with vertices P(2,2)P(2, 2)P(2,2), Q(6,−1)Q(6, -1)Q(6,−1) and R(7,3)R(7, 3)R(7,3). The equation of the line passing through (1,−1)(1, -1)(1,−1) band parallel to PS is :
  1. A
    4x+7y+3=04x + 7y + 3 = 04x+7y+3=0
  2. B
    2x−9y−11=02x - 9y - 11 = 02x−9y−11=0
  3. C
    4x−7y−11=04x - 7y - 11 = 04x−7y−11=0
  4. D
    2x+9y+7=02x + 9y + 7 = 02x+9y+7=0
View written solutionFree

Correct answer: D

  1. Find the midpoint SSS of QRQRQR

Since PSPSPS is a median, point SSS is the midpoint of Q(6,−1)Q(6,-1)Q(6,−1) and R(7,3)R(7,3)R(7,3).

S=(6+72,−1+32)=(132,1)S = \left(\frac{6+7}{2},\frac{-1+3}{2}\right)=\left(\frac{13}{2},1\right)S=(26+7​,2−1+3​)=(213​,1)
  1. Find the slope of PSPSPS

Points on PSPSPS are P(2,2)P(2,2)P(2,2) and S(132,1)S\left(\frac{13}{2},1\right)S(213​,1).

So the slope is

m=1−2132−2=−192=−29m = \frac{1-2}{\frac{13}{2}-2} = \frac{-1}{\frac{9}{2}} = -\frac{2}{9}m=213​−21−2​=29​−1​=−92​
  1. Equation of the line parallel to PSPSPS and passing through (1,−1)(1,-1)(1,−1)

A line parallel to PSPSPS has the same slope −29-\frac{2}{9}−92​.

Using point-slope form through (1,−1)(1,-1)(1,−1):

y−(−1)=−29(x−1)y-(-1)= -\frac{2}{9}(x-1)y−(−1)=−92​(x−1) y+1=−29(x−1)y+1 = -\frac{2}{9}(x-1)y+1=−92​(x−1)

Multiply by 999:

9y+9=−2x+29y+9 = -2x+29y+9=−2x+2 2x+9y+7=02x+9y+7=02x+9y+7=0
  1. Match with the options

The equation obtained is

2x+9y+7=02x+9y+7=02x+9y+7=0

This is Option D.

  1. Comparison with stored correct answer

Stored correct answer: D

Our derived answer: D

So they agree.

PreviousNext

More from Straight Lines and Pair of Straight Lines

  • The x-coordinate of the incentre of the triangle that has the coordinates of mid points of its sides as (0,1)(1,1) and (1,0) is :2013 · MCQ
  • A ray of light along x+3​y=3​ gets reflected upon reaching X-axis, the equation of the reflected ray is :2013 · MCQ
  • If the line 2x+y=k passes through the point which divides the line segment joining the points (1,1) and (2,4) in the ratio 3:2, then k equals :2012 · MCQ
  • The line L given by 5x​+by​=1 passes through the point (13,32). The line K is parrallel to L and has the equation cx​+3y​=1. Then the distance between L and K is :2010 · MCQ
  • The lines p(p2+1)x−y+q=0 and (p2+1)2x+(p2+1)y+2q =0 are perpendicular to a common line for :2009 · MCQ
  • The shortest distance between the line y−x=1 and the curve x=y2 is :2009 · MCQ
  • The perpendicular bisector of the line segment joining P(1, 4) and Q(k, 3) has y-intercept -4. Then a possible value of k is :2008 · MCQ
  • Let A (h,k), B (1,1) and C (2,1) be the vertices of a right angled triangle with AC as its hypotenuse. If the area of the triangle is 1 square unit, then the set of values which ′k′ can take is…2007 · MCQ