Straight LineHardBloom L3
Question
If the line $y = mx$ meets the lines $x + 2y - 1 = 0$ and $2x - y + 3 = 0$ at the same point, then $m$ is equal to :
Options
A.1
B.-1
C.2
D.-2
Solution
Sol. [Key Concept: Three concurrent lines: substitute the intersection of two lines into the third to solve for $m$.]
$y - mx = 0,x + 2y - 1 = 0$ and $2x - y + 3 = 0$ are concurrent
$$\Rightarrow \left| \begin{matrix} m & - 1 & 0 \\ 1 & 2 & - 1 \\ 2 & - 1 & 3 \end{matrix} \right| = 0 = 5m + 5 \Rightarrow m = - 1$$
Create a free account to view solution
View Solution FreeMore Straight Line Questions
A straight line $L$ drawn through the point $A(1,2)$ intersects the line $x + y = 4$ at a distance of $\frac{\sqrt{6}}{3...The equation of perpendicular bisector of the line segment joining the points (1, 2) and (−2, 0) is -...The equation of the line which passes through (a cos3θ, a sin3θ) and perpendicular to the line x secθ + y...The angle between the lines 2x + 3y = 5 and 3x − 2y = 7 is -...Let L1 be a straight line passin through the origin and L2 be the straight line x + y = 1. If the ntercepts made by the ...