How to Find the Slope of a Line
In this session we are going to learn How to Find the Slope of a Line. A line is the collection of points, when we join all these points then we get a line in which the start and the end points are not same. A straight line is the smallest distance between two points. The slope of a line is very important property of a line. This is all about how a straight line angles away from the x axis or horizontal. This is known as slope of a line.
Now the equation of line is y = m*x + c.
Then to find the slope of the line m = change in y / change in x.
Here the change in x = (x2 – x1), and the change in y = (y2 – y1).
If the line passes through points (x1, y1) and (x2, y2) with a slope m the equation of line is
(y2 – y1) = m * (x2 – x1)
Then the slope m = (y2 – y1) / (x2 – x1).
To find the slope of a line just remember one thing that always subtract the x’s and y’s in the same order, never alter their order while subtracting.
Now we will take some examples to understand the basic concept of this.
Suppose we need to find the slope of a line that passes through (1, 3) and (2, -5) then
As we know that slope of a line is m = (y2 – y1) / (x2 – x1)
m = (-5 - 3) / (2 - 1)
m = (-8) / 1
m = 1
so here we get m = 1 for the line which is passing through points (1, 3) and (2, -5).
Similarly if we have a equation y = 2x – 5 then the slope of the given equation is 2 that means the y increases 2 units as 1 unit increases of x that is the rate of change in magnitude of y and x.
Consider one more example where the equation of line is y = -(2/5)*x + 10 then the slope of the given line is 2/5 which means that the y decreases by 2 units for each and every 5 units of x.
A straight line is perpendicular to the other straight line if
1. If the slope of both the lines have opposite signs. One slope has positive sign then other has negative sign.
2. If these two lines are reciprocals of each other.
If two lines are perpendicular then the product of their slopes is always -1. So if the slope of a line is m then the slope of perpendicular line is -1/m.
For example if a line is having slope 5, then every line that is perpendicular to it has slope −1/5.
Similarly if a line has an equation y = 6x – 2 then the slope of the perpendicular line will be -1/6.
So we can find out the slope of a line by using the concept mentioned above in this article.
About the Author
 |
sky walker "In order to get help on binomial expansion calculator and Finding Slope of a Line visit TutorVista.com" |