Final answer:
To find the equation that models the number of items sold, we can set up a system of equations using the given information. Solving the system of equations, the equation that models the number of items sold for x dollars per item is y = -2x + 26.
Step-by-step explanation:
In order to find the equation that models the number of items sold, we can use the given information and set up a system of equations.
From the first piece of information, we know that when the price is $7 per item, 12 items are sold. This can be represented as the equation x = 7, y = 12, where x is the price per item and y is the number of items sold.
From the second piece of information, we know that when 10 items are sold for $9 per item. This can be represented as the equation x = 9, y = 10.
By setting up the system of equations, we can solve for the equation that models the number of items sold for x dollars per item. The system of equations is:
7 = x, 12 = y
9 = x, 10 = y
Solving this system of equations, we find that the equation to model the number of items sold for x dollars per item is y = -2x + 26.