Question

6. Moe and Curly went to Best Buy. Moe bought four CDs and five DVDs and

paid $123. Curly bought two CDs and four DVDs and paid $84. What is the
cost of one CD? What is the cost of one DVD?
(Can y’all help me out real quick please)
How do I write my two equations for this??

Answer 1

Answer: one CD cost $12 and one DVD cost $15 .

Explanation:

In this situation we will represent the cost o one CD by x and the number of one DVD by y. Four CDs plus five DVDs cost 123 so we will represent it by the equation 4x + 5y = 123

The same or the second part of the statement. 2 CDs plus 4 DVDs cost $84 so we will also represent that by the equation , 2x + 4y = 84

Since we have two equations we will use it to solve or x and y using the elimination method.

4x + 5y = 123

2x + 4y = 84 Multiply the down equation by -2 to eliminate the x variable.

-2(2x + 4y ) = -2(84)

-4x -8y = -168

We will now have the new equations ,

4x + 5y = 123

-4x - 8y = -168 Add both equations to

-3y = -45

y= 15

This means each DVD cost $15 .

Now we will now have to solve for x by plotting in the value of y into the equation .

4x + 5(15) = 123

4x + 75 = 123

-75 -75

4x = 48

x = 12

This also means that one CD cost $12.