The Pool Fun Company has learned that by pricing a newly rel

The Pool Fun Company has learned that, by pricing a newly released Fun Noodle at

$ 3 comma

sales will reach

9000

Fun Noodles per day during the summer. Raising the price to

$ 6

will cause the sales to fall to

6000

Fun Noodles per day.

a. Assume that the relationship between sales price, x, and number of Fun Noodles sold, y, is linear. Write an equation in slope-intercept form describing this relationship. Use ordered pairs of the form (sales price, number sold).

Solution

(sales price, number sold).

So, the two ordered pairs are :
(3 , 9000) and (6 , 6000)

Slope = (y2 - y1) / (x2 - x1)

m = (6000 - 9000) / (6 - 3)

m = -1000

So, we have y = -1000x + b

And using the point (3,9000), we can find b :
9000 = -1000(3) + b
9000 = -3000 + b
b = 12000

So, we have :

y = -1000x + 12000 ----> ANSWER
where y ---> number sold
and x --> Sales price in dollars