my math that i am doing i am having a hard time with +2-4 and its asking me to find the slope on my graph i dont know how to read a graph

Question

how do i know what a slope is on a graph

Answer 1

Hi, Rachel.

A graph is on a grid known as the "coordinate plane." We locate and name points on the graph as (x,y) meaning that we count x units from zero on the x-axis (going across) and y units up or down.

If you have a line drawn on a graph, find 2 places where the line goes directly through a "cross" and find the coordinates (x,y) of those points. You can then find the slope by finding the difference between them.

As another tutor said, the slope is "rise over run" so it is the opposite of how we name points. You can find slope on a graph by starting from one point on a line and counting units up/down then left/right to get to another point on the line.

You can also find slope using the coordinates of two points, (x₁, y₁) and (x₂,y₂). The slope is the difference of the y's over the difference of the x's, that is:

y₂ - y₁
--------
x₂ - x₁

The slope is written as a fraction or integer.

I hope this helps you!

Answer 2

Another term often used to describe "slope" is "rise over run".  What this means is that you choose two points on the graph of a line (any two will do), and you divide their "vertical distance" by their "horizontal distance".  

So if you have two points (X₁, Y₁) and (X₂, Y₂) then the formula is:

Y₂ - Y₁
--------
X₂ - X₁

For example, if you have two points on your line (1, 2) and (3, 6), then the slope would be:

6 - 2       4
------  =  ---  =  2
3 - 1       2