We want to find a linear equation that models the given situation.
The solution is p = $0.0001*q - $23
The general linear equation is:
p = m*q + c
Where m is the slope and c is the y-intercept.
If we know that the line passes through two points (x₁, y₁) and (x₂, y₂) then the slope can be written as:
Here we have the two points:
price = $9, boxes = 320,000
price = $8.50, boxes = 270,000
We can rewrite these as:
(320,000 , $9)
(270,000 , $8.50)
Then the slope of the line will be:
Then the line is something like:
p = $0.0001*q + c
To find the value of c we can use one of the two given points, I will use the first one, (320,000 , $9).
Replacing that in our equation we get:
$9 = $0.0001*320,000 + c
$9 - $0.0001*320,000 = c = -$23
Then the linear equation is:
p = $0.0001*q - $23
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