$\"\"$

The equation $\"\"$ represents a constant rate of change and k is the constant of variation.

Compare the equation $\"\"$ with equation $\"\"$ .

The constant of variation is $\"\"$ . $\"\"$

The slope m of a non vertical line through any two points is given by,

$\"\"$

Substitute $\"\"$ .

$\"\"$

Slope $\"\"$ . $\"\"$

The slope m of the line that passes through the pair of points is $\"\"$ .