Ask Questions, Get Answers

Home  >>  JEEMAIN and NEET  >>  Mathematics  >>  Class11  >>  3-D Geometry

A line with direction ratio $(2,1,2)$ meets the lines $x=y+a=z\:\;and\:\:x+a=2y=2z$. The coordinates of the points of intersections are ?

$\begin{array}{1 1} (a)\:(2a,3a,a)\: and\: (2a,a,a)\:\:\qquad\:(b)\:(3a,2a,3a)\: and\:(a,a,a)\:\:\qquad\:(c)\:(3a,2a,3a)\:and\:(a,a,2a)\:\:\qquad\:(d)\:(3a,3a,3a)\: and\: (a,a,a) \end{array} $

1 Answer

Out of the four options, option $ (b) \: (3a,2a,3a)\:and\:(a,a,a)$ is the correct answer.
Because these two points satisfy the given two lines respectively and
also the $d.r.$ of the line $(2,1,2)$ is proportional to $(3a-a,\:2a-a,\:3a-a)$
answered Jan 6, 2014 by rvidyagovindarajan_1

Related questions