Jerry bought 2 DVDS and 5CDs for $65. Next month he bought 4 DVDs and 3 CDs. How much did CDs and DVDs cost

Answer 1

This question should be solved using a system of two equations. However, Mia needs to provide what Jerry paid for the second set of CDs and DVDs to able to complete this problem.

Ok. So Jerry paid $81 for the second set of CDs and DVDs. Let C= # of CDs and D= # of DVDs.

then,

2D + 5C = 65 and

4D + 3C = 81.

Using elimination, multiply the top equation by -2 which results in

-4D - 10C = -130 and

4D + 3C = 81

Add the two equations,

-7C = -49

so C = 7, plug 7 for C back into the original bottom equation.

4D + 3(7) = 81, Solve for D. Subtract 21 from both sides of the equation

4D + 21 - 21 = 81 - 21

Then

4D = 60, D = 15

So, the CDs cost $7 and the DVDs cost $15