Respuesta :

Answer:

Part A: [tex]12x+15y<120[/tex]

Part B: B,C, and E

Step-by-step explanation:

Part A:

Since the cost of each book is $12, and x is the number of books, the total cost of books will be 12x.,

Similarly, since the cost of each DVD is $15, and y is the number of DVDs, the total cost of DVDs will be 15y.

Thus, the total cost of books and DVDs will be 12x + 15y.

We know that the total cost was less than $120, so this expression should be less than 120.

Thus, the inequality is:

[tex]12x+15y<120[/tex]

Which corresponds to alternative B.

Part B:

To check whether the amount in the alternatives can be purchased, we just need to substitute x and y and check whether the inequality is valid:

I'm going to work out these equations :)

Option A.

[tex]12~x~5+15~x~5<120(?)[/tex]

[tex]60+75<120(?)[/tex]

[tex]135<120-->~invalid[/tex]

Option B

[tex]12~x~6+15~x~2<120(?)[/tex]

[tex]102<120--> ~valid[/tex]

Option C.

[tex]12~x~2+15~x~6<120(?)[/tex]

[tex]114<120(?)-->~valid[/tex]

Option D.

[tex]12~x~0+15~x~10<120(?)[/tex]

[tex]0+150<120(?)[/tex]

[tex]150<120-->~invalid[/tex]

Option E

[tex]12~x~8+15~x~0<120(?)[/tex]

[tex]96+0<120(?)[/tex]

[tex]96<120--->~Valid[/tex]

Thus, the amounts that could have been purchased are those in alternatives B, C and E.