Question

POSSIBLE POINTS. 7 Two clothing stores are having a sale on all their dress shirts. Store A is charging $15 for each dress shirt. Store B is $18 for each shirt but giving customers a coupon for a $9 discount when they check out. Which of the following statements are true? There can be more than one correct answer.​

Answer 1

The statements are not provided, so i will answer in a general way.

Let's define the variable x as the number of dress shirts brought for some person.

In store A, each one costs $15.

Then the cost of x dress shirts will be:

A(x) = $15*x.

In store B, each one costs $18, but there is a coupon of $9, then we can write the cost in store B as:

B(x) = $18*x - $9.

Now we can find wich store will be cheaper for a given number x, by calculating the difference between A(x) and B(x).

D = A(x) - B(x)

If D is positive, means that B(x) is cheaper.

If D is negative, means that A(x) is cheaper.

If D is equal to zero, means that the cost is the same in both stores.

D = A(x) - B(x) = $15*x - $18*x + $9 = (-$3*x) + $9.

First, let's find for what value of x we have the same cost in both stores:

0 = (-$3*x) + $9.

$9/$3 = 3 = x.

Then for 3 dress shirts, the cost will be the same in each store.

Now, as the coefficient that multiplies x is negative, if we have x > 3, then D will be negative, and if x < 3, D will be positive.

then:

For x = 3, the cost is the same in both stores.

for x > 3, Store A is cheaper.

For x < 2, Store B is cheaper.