Question

Find the equation of the line containing point A(4, 3) and having inclination 120°

Answer 1

Given, Inclination of line = θ = 120°

∴ Slope of the line (m) = tan θ

= tan 120°

= tan (90° + 30°)

= – cot 30°

= `-sqrt(3)`

and the line passes through A(4, 3).

Equation of the line in slope point form is

y – y₁ = m(x – x₁)

∴ The equation of the required line is

y – 3 = `-sqrt(3)("x" - 4)`

∴ y – 3 = `-sqrt(3) "x" + 4sqrt(3)`

∴ `sqrt(3) "x" + "y" - 3 - 4sqrt(3)` = 0