Quantcast

Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonnnn

I have to solve the system 7x - 3y = 20 5x + 3y = 16 I solved it once; 7x - 3y = 20 + 5x + 3y = 16 = 12x = 36 = x = 3 7(3) = 3y = 20 = 21 - 3y = 20 21 - 21 - 3y = 21 - 21 = 3y = -1 = y = 1/3 so (3, 1/3) But I cant figure out how to solve it for a nother way and get the same answer.

  • one year ago
  • one year ago

  • This Question is Closed
  1. FZ6628
    Best Response
    You've already chosen the best response.
    Medals 0

    Example: 2X+6Y=10 3X-2Y=12 There is another method called substitution, in which you manipulate one of the equation to isolate a variable. For example 2X+6Y=10 can be manipulated into X=5-3Y Then you substitute the second part of the equation, 5-3Y in the second equation, 3X-2Y=12, resulting in 3(5-3Y)-2Y=12. Then you can use simple algebra to figure out X and Y

    • one year ago
  2. anonnnn
    Best Response
    You've already chosen the best response.
    Medals 0

    I know about substitution, and I have attempted it several times in several different manners but I cannot come up with the same answer as the first.

    • one year ago
  3. anonnnn
    Best Response
    You've already chosen the best response.
    Medals 0

    If at all.

    • one year ago
  4. Hero
    Best Response
    You've already chosen the best response.
    Medals 0

    There's at least five different ways of solving these 1. Graphing 2. Substitution 3. Elimination 4. Matrices 5. Cramer's Method Pick one

    • one year ago
  5. Hero
    Best Response
    You've already chosen the best response.
    Medals 0

    There's also slope-intercept method as well

    • one year ago
    • Attachments:

See more questions >>>

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.