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

axelneel

Identify the 42nd term of an arithmetic sequence where a1 = -12 and a27 = 66

  • 10 months ago
  • 10 months ago

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

    i keep coming up with 126 but my options are 70,72,111,114. PLEASE HELP

    • 10 months ago
  2. RaphaelFilgueiras
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1372218335949:dw|

    • 10 months ago
  3. Jhannybean
    Best Response
    You've already chosen the best response.
    Medals 1

    \[\large a_{n}= a_{1}+(n-1)d\]

    • 10 months ago
  4. RaphaelFilgueiras
    Best Response
    You've already chosen the best response.
    Medals 1

    r=3

    • 10 months ago
  5. RaphaelFilgueiras
    Best Response
    You've already chosen the best response.
    Medals 1

    111

    • 10 months ago
  6. RaphaelFilgueiras
    Best Response
    You've already chosen the best response.
    Medals 1

    find r and then just plug in that first equation

    • 10 months ago
  7. Jhannybean
    Best Response
    You've already chosen the best response.
    Medals 1

    \[\large 66 =-12+(27-1)d \]\[\large 66= -12 +26d\]\[\large 78 = 26d\]\[\large d= 3\] \[\large a_{42} = -12 + 3(42-1)\]\[\large a_{42} = -12 + 123\]\[\large a_{42} = 111\]

    • 10 months ago
  8. axelneel
    Best Response
    You've already chosen the best response.
    Medals 0

    i have no idea what i was doing wrong... but thank you

    • 10 months 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.