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Question
A straight line L through the point (3, –2) is inclined at an angle of 60° to the line `sqrt(3)x + y` = 1. If L also intersects the x-axis, then the equation of L is ______.
Options
`y + sqrt(3)x + 2 - 3sqrt(3)` = 0
`sqrt(3)y + x - 3 + 2sqrt(3)` = 0
`y - sqrt(3)x + 2 + 3sqrt(3)` = 0
`sqrt(3)y - x + 3 + 2sqrt(3)` = 0
Solution
A straight line L through the point (3, –2) is inclined at an angle of 60° to the line `sqrt(3)x + y` = 1. If L also intersects the x-axis, then the equation of L is `underlinebb(y - sqrt(3)x + 2 + 3sqrt(3) = 0)`.
Explanation:
Given equation of line is `y + sqrt(3)x - 1` = 0
⇒ y = `-sqrt(3)x + 1`
⇒ (Slope)m2 = `-sqrt(3)`
Let the other slope be m1
∴ tan 60° = `|(m_1 - (-sqrt(3)))/(1 + (-sqrt(3)m_1))|`
⇒ m1 = 0, m2 = `sqrt(3)`
Since line L is passing through (3, –2)
∴ y – (–2) = `+ sqrt(3)(x - 3)`
⇒ y + 2 = `sqrt(3)(x - 3)`
`y - sqrt(3)x + 2 + 3sqrt(3)` = 0