Question

Slope of the line parallel to y-axis is.

• A. 1
• B. ${90}^{\circ }$
• C. undefined
• D. ${180}^{\circ }$

Answer 1

The correct option is C undefined

Slope of a line $=m=\tan \theta$

where $\theta$ is the angle made by the line with the $x-$axis.

For a line parallel to $y-$axis ,$\theta =\frac{\pi }{2}$

$\therefore m=\tan \frac{\pi }{2}=$undefined