Problema Solution

A vendor learned that by pricing pretzels at $1.75, sales will reach 119 pretzels per day. Raising the price to $2.75 will cause the sales to fall to 79 pretzels per day. Let Y be the number of pretzels the vendor sells at X dollars each. Write the liner equation that models the number of pretzels sold per day when the price is X dollars each.

Answer provided by our tutors

Basically you have two points:

(1.75, 115) and (2.75, 75)


Find the slope (m) using the formula you should have in your book.


Then use the slope (m) and one of the points in this formula:


y - y1 = m(x - x1).


Try it out. I'll post the answer in a little bit (although chances are someone else will... I like to make people try it on their own after explaining how).