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

huntaz556

how to do 7x - 3y = 20 ---------- 5x + 3y = 16 with elimination?

  • 2 years ago
  • 2 years ago

  • This Question is Closed
  1. Mrs.Math101
    Best Response
    You've already chosen the best response.
    Medals 1

    the 3y cancels out, so 7x+5x=12x and 20+16= 36so the new equation is 12x=36

    • 2 years ago
  2. ravi623
    Best Response
    You've already chosen the best response.
    Medals 3

    add two equations and u will get 12x=36 so x=3, put this value of x in any equation, u will get the value of y

    • 2 years ago
  3. huntaz556
    Best Response
    You've already chosen the best response.
    Medals 0

    I thought with elimination you were supposed to multiply one of the equations to make it the same as the other? Im not completely sure thats why i asked here :P

    • 2 years ago
  4. GT
    Best Response
    You've already chosen the best response.
    Medals 0

    Well, you do need to multiply one or both equations to make the coefficient of one of the variables same (constant before the variable). In this case, the coefficient of y is already the same (3). So, you don't need to multiply to do elimination.

    • 2 years ago
  5. GT
    Best Response
    You've already chosen the best response.
    Medals 0

    If you had for example x + 2y = 5 2x + y = 7 Then, you will have to multiply the second equation by 2 to eliminate y. Or, multiply the first equation by 2 to eliminate x.

    • 2 years ago
  6. sunsetlove
    Best Response
    You've already chosen the best response.
    Medals 1

    good work

    • 2 years 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.