SOLUTION: Suppose there is a linear relationship between price and demand for an object. Demand for a video game is 1000 units when the price is $40 and 2000 units when the price is $20?

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Question 1037782: Suppose there is a linear relationship between price and demand for an object. Demand for a video game is 1000 units when the price is $40 and 2000 units when the price is $20?
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The description gives two points on a line, (x,y) for Demand for y and Price for x, if you want those ways to assign the quantities. These would be the points (40,1000) and (20,2000). Find the line which fits the form y=mx+b.

y-mx=b
b=y-mx
Pick either point.
b=1000-%28%282000-1000%29%2F%2820-40%29%2940
b=1000-%281000%2F%28-20%29%29%2A40
b=1000%2B%28100%2F2%29%2A40
b=1000%2B50%2A40
b=1000%2B2000
b=3000
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Look into one of the steps to see m=-50.
highlight%28y=-50x%2B3000%29

That is not the only way to solve the example. I used only slope-intercept form, but the point-slope form can be used instead and later adjusted to slope-intercept form. Which way to assign the variables and what "names" for variables you use can be changed. I chose x and y and assigned as done. This was DEMAND as a function of unit price.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

Suppose there is a linear relationship between price and demand for an object. Demand for a video game is 1000 units when the price is $40 and 2000 units when the price is $20?
As price is the DEPENDENT variable, and quantity demanded, the INDEPENDENT variable, the equation is: highlight_green%28y+=+%28-+1%2F50%29x+%2B+60%29