Question

Lisa has developed a new product, and knows that the graph of function R models her revenue from selling the item, after deducting expenses, when she charges x dollars per unit.

Lisa wants to restrict function R to only model selling prices for which she will make a profit. Which interval should she use as the domain of the function?

Answer 1

Choice B is correct; (10, 60)

Explanation:

For Lisa to make a profit, the function R should assume a value greater than 0;

R > 0

We are to determine the interval of x values for which the above expression will be true.

From the graph, R(x) = 0 when x = 10. As x increases from 10 to 60, the value of R(x) remains positive, that is;

R(x) ≥ 0 for values of x in the interval (10, 60)

The domain that she should use in order to only model selling prices for which she will make a profit is thus;

(10, 60)