Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

Trending News

Promoted
Roberta
Roberta asked in Science & MathematicsMathematics · 1 decade ago

How do you do the following problem?

the sum of two decimal numbers is 3.9. their difference is 0.9 and their product is 3.6. What are the two numbers?

2 Answers

Relevance
  • Michael B
    1 decade ago
    Favorite Answer

    x + y = 3.9

    x * y = 3.6

    x * (3.9 - x) = 3.6

    3.9x - x^2 = 3.6

    x^2 - 3.9x +3.6 = 0

    using quadratic formula

    x = (3.9 + or - sqrt(3.9^2 - 4(3.6)))/2

    x = 1.5 or 2.4

    There are two possible solutions:

    x is 1.5 y is 2.4

    x is 2.4 y is 1.5

  • Anonymous
    1 decade ago

    x + y = 3.9

    x - y = 0.9

    2y = 4.8

    y = 2.4

    x + 2.4 = 3.9

    x = 1.5

    so the two numbers are 2.4 and 1.5

    to prove is 2.4 x 1.5 = 3.6

Still have questions? Get your answers by asking now.