Q. The orthocenter of a triangle formed by the lines $x + y = 1,\ 2x + 3y = 6$ and $4x - y + 4 = 0$ lies in the

A) $Ist$ quadrant
B) IInd quadrant
C) IIIrd quadrant
D) IVth quadrant
Explanation

(a)
On solving line Ist and IInd, and Ist and IIIrd, we get $A( - 3,4)\$and $B\left( - \frac{3}{5},\frac{8}{5} \right)$.
[image:10_image16.emf]
The equation of perpendicular line to the line $4x - y + 4 = 0$ and passes through the point $A( - 3,\ 4)$ is
$x + 4y - 13 = 0$ …(i)
Also, the equation of perpendicular line to the line $2x + 3y = 6$ and passes through $a\ point\ B\left( - \frac{3}{5},\frac{8}{5} \right)\ is\$
$3x - 2y + 5 = 0$ …(ii)
On solving Eq. (i) and (ii), we get the orthocentre $\left( \frac{3}{7},\frac{22}{7} \right)$
Which is lies in Ist quadrant.

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.