A general linear equation is given by:
Where a is the slope and b is the y-intercept.
Here we will find that the linear equation that represents the situation is
And we can expect that the median salary in 2048 is $2.853 million
If the line passes through the points (x₁, y₁) and (x₂, y₂) then the slope can be written as:
Here we know that:
in 2007 (x = 7) the median player salary was y = $1.5 million
in 2013 (x = 13) the median player salary was y = $1.7 million.
Then we have two points that we can write as:
(7, 1.5)
(13, 1.7)
Note that the y-value is in millions.
Then the slope of the linear equation will be:
So the linear equation is something like:
To find the value of b, remember the point (7, 1.5), this means that when we have x = 7, we also have y = 1.5, then we can replace these in the above equation:
Then the linear equation is:
b) Now we want to predict the median salary in 2048. For 2048 the x-value is x = 48
So we just need to evaluate this in the linear equation:
Then the median salary in 2048 will be $2.853 million
If you want to learn more, you can read: