Straight Line Question 13

Question: The line passes through (1, 0) and $ (-\ 2,\ \sqrt{3}) $ makes an angle of …… with x?axis [RPET 1985]

Options:

A) $ 60^{o} $

B) $ 120^{o} $

C) $ 150^{o} $

D) $ 135^{o} $

Show Answer

Answer:

Correct Answer: C

Solution:

  • Gradient of the line which passes through (1, 0) and $ (-2,\sqrt{3}) $ is $ m=\frac{\sqrt{3}-0}{-2-1}=-\frac{1}{\sqrt{3}} $
    Þ $ \theta ={{\tan }^{-1}}( -\frac{1}{\sqrt{3}} )=150^{o} $ .