Question

If a line makes an angle of ${30}^{\circ }$ with the positive direction of $y-$ axis measured in anticlockwise direction, then the slope of the line is

• A. $\sqrt{3}$
• B. $-\sqrt{3}$
• C. $\frac{1}{\sqrt{3}}$
• D. $-\frac{1}{\sqrt{3}}$

Answer 1

The correct option is B $-\sqrt{3}$

If a line makes an angle of ${30}^{\circ }$ with positive direction of the $y-$ axis measured in anticlockwise direction, then plotting the line, we get


Thus, the slope of the given line is
$m=\tan {120}^{\circ }=-\tan {60}^{\circ }=-\sqrt{3}$