Question

Equation of the line passing through the point $(1,2)$ and perpendicular to the line $y=3x-1$ is

• A. $x+3y-7=0$
• B. $x+3y+7=0$
• C. $x+3y=0$
• D. $x-3y=0$

Answer 1

The correct option is A $x+3y-7=0$

Slope of the line $y=3x-1$ is $3$.
Slope of the line perpendicular to the given line will be $-\frac{1}{3}$
Equation of the line passing htrough $(1,2)$ and having slope $-\frac{1}{3}$ is :$x+3y-7=0$