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

Kellie13 Group Title

4(x+y)=x-16

  • 2 years ago
  • 2 years ago

  • This Question is Open
  1. Kira_Yamato Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    4(x+y) = x-16 4x+4y = x-16 3x+4y = -16

    • 2 years ago
  2. Kellie13 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    the rest of the equation I forgot to place in: -3(x-y)=y+10

    • 2 years ago
  3. richyw Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    So you have this system of equations\[4(x+y)=x-16\]\[-3(x-y)=y+10\]First solve the first equation for one of the variables\[4x+4y=x-16\]\[4y=-3x-16\]\[y=-\frac{3}{4}x-4\]Now plug that value into the second equation and solve for the second variable\[-3x+3y=y+10\]\[-3x+2y=10\]\[-3x+2\left(-\frac{3}{4}x-4\right)=10\]\[-3x-\frac{3}{2}x-8=10\]\[\frac{-6-3}{2}x=18\]\[-\frac{9}{2}x=18\]\[x=-4\]Now plug that value of x into either equation to solve for y.\[4(x+y)=x-16\]\[4(-4+y)=-4-16\]\[-16+4y=-20\]\[4y=4\]\[y=1\]So the solution is x=-4, y=1

    • 2 years ago
  4. richyw Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    oops, should be -1/

    • 2 years ago
  5. richyw Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    the second last line I dropped the negative it should say \[4y=-4\]\[y=-1\]So the solution is x=-4, y=-1

    • 2 years ago
  6. dpgreen Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    just to let you know, you dont only have to do the substitution process, you can also do elimination. 4(x+y)=x−16 −3(x−y)=y+10 distribute to get 4x+4y=x−16 -3x+3y=y+10 the subtract the common terms from each other to get final answer

    • 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.