Question

Find the slope of the line, which makes an angle of 30° with the positive direction of y-axis measured anticlockwise.

Answer 1

If a line makes an angle of 30° with the positive direction of the y-axis measured anticlockwise, then the angle made by the line with the positive direction of the x-axis measured anticlockwise is 90° + 30° = 120°.

Thus, the slope of the given line is tan 120° = tan (180° - 60°) = - tan 60° = $-\sqrt 3$