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

ttsmith7394 Group Title

hey, im in 9th and need help with algebra; trinomials. if you cold help me that would be great. thanks,

  • 3 years ago
  • 3 years ago

  • This Question is Closed
  1. 3pwood Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    What do you need help with, specifically?

    • 3 years ago
  2. ttsmith7394 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    r(square) + 2r = 24

    • 3 years ago
  3. 3pwood Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Solving for r? There are so many ways of doing this it's not even funny. Here are a few: Quadratic equation: http://en.wikipedia.org/wiki/Quadratic_equation r^2 + 2r - 24 = 0 so r = [-2 ± sqrt(2^2 - 4*1*(-24))] / [2*1] r = 4 or -6 Completing the square: r^2 + 2r = -24 r^2 + 2r + (2/2)^2 = 24 + (2/2)^2 r^2 + 2r + 1 = 25 (r + 1) ^ 2 = 25 r + 1 = ±sqrt(25) r + 1 = ±5 r = -1 ±5 r = 4 or -6 Seat-of-the-Pants Factoring: r^2 + 2r - 24 = 0 (try to find two numbers that sum to 2 and multiply to -24) -1 * 24 = -24 but they don't sum to 2 -3 * 8 = - 24 but they dont' sum to 2 -4 * 6 = - 24 and they do sum to 2. That's the set we need. so this expression can be factored like so: (r^2 + 2r - 24 = (r - 4)(r+6) And this new expression will only equal zero if one of the terms in parentheses equals zero. That'll only happen at r = 4 or -6

    • 3 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.