Post a New Question

Math.

posted by on .

Kate bought 3 CDs and 1 DVD at a store. Her friend Joel bought 2 CDs and 2 DVDs. If Kate spent $20 and Joel spent $22, determine the cost of a CD and DVD.
~Please provide an explanation as well.
Please and thanks!

  • Math. - ,

    cost of CD --- x
    cost of DVD -- y

    3x + y = 20 ---> y = 20-3x

    2x + 2y = 22
    x +y = 11
    use substitution:
    x + (20-3x) = 11
    -2x = -9
    x = 4.5
    then y = 6.5

Answer This Question

First Name:
School Subject:
Answer:

Related Questions

More Related Questions

Post a New Question