Back to STRAIGHT LINES

JEE MATHEMATICS MCQ: STRAIGHT LINES

1 Medium

1 of 1

Application +4 | -1

Let

L_1

be a tangent to the parabola

y^2=4(x+2)

and

L_2

be a tangent to the parabola

y^2=8(x+3)

such that

L_1

and

L_2

intersect at right angles, then

L_1

and

L_2

meet on the straight line

View answer and explanation

Correct option: A

x+4=0

Option A (

x+4=0

) is correct because the tangents intersect at right angles, which implies that the directrices of the parabolas intersect at the point of intersection of the tangents. The directrices are x = -4 and the intersection point lies on the line x = -4 or x + 4 = 0.

More Questions from STRAIGHT LINES

Practice All Chapter MCQs →

If the three lines

x-3 y=p, a x+2 y=q

a x+y=r

form a right-angled triangle then :
The orthocentre of the triangle whose vertices are

\left\{ {a{t_1}{t_2},\;a\left( {{t_1} + {t_2})\} ,\{ a{t_2}{t_3},a({t_2} + {t_3}} \right)} \right\},\;\left\{ {a{t_3}{t_1},\;a\left( {{t_3} + {t_1}} \right)} \right\}

is
The distance between the parallel lines

y = 2\;x + 4

6x = 3y + 5

is The distance between the pair of lines given by

{x^2} + {y^2} + 2xy - 8ax - 8ay - 9{a^2} = 0

is Find the image of the point

(3,8)

with respect of the line

x+3 y=7

assuming the line to be plane mirror: The centroid of the triangle whose three sides are given by the combined equation

\left( {{x^2} + 7xy + 2{y^2}} \right)\left( {y - 1} \right) = 0