# How do you use the method of linear interpolation to approximate values and create an equation of a line?

##### 1 Answer

Mar 22, 2015

Let's say you have two points:

An equation of the line will be of the form

where

**Example** :

Let's take

graph{0.5x+3 [-9.61, 12.89, -2.795, 8.455]}

Then first we determine the slope

Difference in

Difference in

To find the slope we divide

We fill this in in one of the points to get

So the equation goes

And you can fill in any

**Check** (allways check!) with the other point