the slope of a straight line

Slope of a line :

The Slope of a straight line is defined as that it is described direction and as well as steepness of a line.

Or

The Slope of a line can be defined as that it is changing rate of y with respect to x in x-y plane.

Notation : Generally slope is denoted by m or tanθ .

Slope = m = tanθ .

here θ is an angle between the line and positive direction of x-axis.

Different cases are arise :

slope of a line
the slope of a line
perpendicular to x-axis
parallel to x-axis
    1. slope of a line joining with two points:

Let points A(x1,y1) and B(x2,y2) be the two points .

Slope of a line = m = tanθ

    1. tanθ ( 0< θ𝜋 ) and θ𝜋/2

2. Slope of a line :

        For X-axis –

                           m =  0

For Y-axis –

                           m =  undefined

slope of a line

To check collinearity :

      Let  points P ,Q & R are collinear if and only if

Slope of PQ = Slope of QR = Slope of PR.

 The slope of a line is a sense of independent.

Slope of PQ = Slope of QP

      tanθ = tan( 𝜋 + θ )

 To check parallel :

m1 = m2

To check perpendicular :

m1m2=-1