Question

Find the equation of straight line at an inclination of 120° with the +ve direction of x-axis and having a point (-2,4) on it.

Answer 1

Given θ=120°

and (X1Y1) - (-2,4) The equation of straight line in slope point form is given by Y -Yl = m(x-x1)

or Y -4 = tan 120° (x-(-2))

or Y -4 = tan(180°-60°)[x+2]

or y-4 = -tan60°(x+2)

or y-4 = -√3(x+2) y-4 = -√3x - 2√3

or √3x + y + 2.√3 - 4 = 0 is the required equation of straight line.