Q18 of 169 Page 656

Find the slope of the line which makes an angle of 300 with the positive direction of the y-axis, measured anticlockwise.

According to the given figure, the angle made by the line from X-axis is 90+30 = 120°


We also know that slope of a line is equal to tanθ, Where


θ = 120°


tan(120°) = tan(90°+30°) = -cot(30°) = -√3


Therefor the slope of the given line is -√3.


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