slope or gradient of line passing through two points

slope of line passing through two points:

For the points ( x1,y1) and (x2 ,y2)
slope =y2 - y1/x2 -x1 (Formula)
It means ...
Slope = Difference of y coordinates /Difference of x coordinates

Example :find the slope or gradient of line passing through (3,-2) and (-1,4)
slope =y2 - y1/x2 -x1
slope = 4-(-2) / -1-3 ( x1 = 3,y1 = -2 ,x2 = -1 , y2 = 4, using slope formula)
slope = 4 + 2 / - 4
slope = 6 / -4
slope = -3/2

Practice:
find the slope or gradient of line passing through (2,3) and (4,6)
find the slope or gradient of line passing through (0,-3) and (2,1)
find the slope or gradient of line passing through (1,-2) and (2,-3)
Answers:
3/2
-2
-1

Writing equation from graph

To write an equation in slope-intercept form, given a graph of that equation, pick two points on the line and use them to find the slope.

Slope = Difference of y coordinates /Difference of x coordinates

For the points ( x1,y1) and (x2 ,y2)

slope = y2 - y1/x2 -x1

This is the value of M in the equation. Next, find the coordinates of the y-intercept--this should be of the form (0, b). The y- coordinate is the value of b in the equation.

Finally, write the equation, substituting numerical values in for M and b.
Y = MX + b