Quantcast

A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

CarolineJean

  • 2 years ago

Can someone explain to me, STEP BY STEP how to do this problem please, its Algebra 2-Complex numbers. -6(x+5)^2=120

  • This Question is Closed
  1. hartnn
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    first divide both sides by -6 what u get ?

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

    and u should know that \(\huge \sqrt{-1}=i\)

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

    6(x+5)^2+120 = (x+5)^2 - 20i^2 =0 ( and then factorise ) as i^2 =-1

  4. 1on1
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    hartn good explanation and asking for participation . well done !!

  5. Dido525
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    |dw:1352352097064:dw|

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

    \[-6(x+5)^2=120\]\[(x+5)^2=-\frac{120}{6}\]\[x+5=\sqrt{-\frac{120}{6}}\]\[x+5=\sqrt{-20}\]\[x=\sqrt{-20}-5\]\[x=\sqrt{20}i-5\]\[x=\sqrt{4\cdot 5}i-5\]x=2\sqrt{5}i-5

  7. Dido525
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Now take the square root of the RHS .

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

    \[x=2\sqrt{5}i-5\]

  9. Dido525
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Don't just post the answer...

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

    i don't think @CarolineJean wants any of your solutions, she wants to understand and none of you are helping by giving steps out...

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

    @hartnn yeah, thanks :)

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

    oops just forgot the \(\pm\)

  13. Dido525
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Now take the square root. What do you get?

  14. Dido525
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I don't think you HAVE to simplify...

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

    I dunno it's how I learn. sorry. I will leave.

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

    wow thanks everyone that helped alot :O i have a test tomorrow & didn't know how to do this type of problem but i understand now, thanks ^.^

  17. 1on1
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    you go hartn !

  18. Dido525
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Ohh you understand? :) Good :) .

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

    omg the whole time i was trying to figure out how to do it i was trying to figure out how everyone was getting 20... i feel dumb now.... x)

  20. Dido525
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Haha :) .

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

    if you are following my (huge list) of steps. just don't forget to take bot the positive and negative root. So you should get \(x=-2i\sqrt{5}-5\) and \(x=2i\sqrt{5}-5\)

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

    x=.... OR x=... either of them is a solution, not both

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

    yay ! i got that ! @richyw

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

    thank you to the only 2 ppl that really explained what to do lol @hartnn @richyw

  25. Dido525
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Not me? ;) . Jk Jk . Glad you understood :) .

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

    sorry didn't see yours ! :O @Dido525

  27. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

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.