Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
0 votes

The line $ 2x+3y+9=0$ touches the parabola $y^{2}=8x$ at the point

\[\begin{array}{1 1}(1)(0 , -3)&(2)(2 , 4)\\(3)(-6 , \frac{9}{2})&(4)(\frac{9}{2} ,-6 )\end{array}\]

Can you answer this question?

1 Answer

0 votes
The equation of the parabola is $y^2=8x$
$y^2=4(2) x => a =2$
The equation of the given line is
$y= -\large\frac{2}{3} x -\frac{9}{3}$
$y= -\large\frac{2}{3} x$$ -3$
$m=-\large\frac{2}{3} $$x -3$
The point of contact is $\bigg( \large\frac{2}{(\Large\frac{-2}{3} )^2}. \frac{2 \times 2}{(\Large\frac{-2}{3})} \bigg)$
$\qquad=\bigg( \large\frac{2}{\Large\frac{4}{9} }. \frac{4}{-2} $$ \times 3 \bigg)$
$\qquad= \bigg (\large\frac{9}{2}, -6 \bigg)$
Hence 4 is the correct answer.
answered May 15, 2014 by meena.p
Ask Question
student study plans
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App