Question

Find the angle between the x-axis and the line joining the points (3, -1) and (4, -2).

Answer 1

First we find slope of line joining the points (3, -1) and (4, -2).

We know that slope of line passing through (x₁, y₁) and (x₂, y₂) is

Now, 

Finding Angle from Slope

Now,

Slope = m = tan θ

where θ is the angle between line and positive x-axis.

So,

So, Required angle = θ = 135°.