The two lines lx + my = n and l'x + m'y = n' are perpendicul... | Mathematics | SolveeIt | Solveeit

Today, August 18

Question

The two lines lx + my = n and l'x + m'y = n' are perpendicular if

A

$ll'+mm'=0$

B

$lm'=ml'$

C

$lm+l'm'=0$

D

$lm'+ml'=0$

Answer

$ll'+mm'=0$

Explanation

Solution

The correct answer is (A) : $ll'+mm'=0$ .