A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

Medal for Matrix help. How would I solve for x? [-8 -14 -2x] = [2 -74 -6]

  • This Question is Closed
  1. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    what row by column matrix is this?

  2. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    1 x 3 for both

  3. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    so is A - [-8 -14 2x] and B =[2 -74 -6]?

  4. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    it's like find an x that will make both matrices equal...

  5. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Yeah, that's the issue. I have no idea how to find x in this situation. It's been a while since I've done a problem like this.

  6. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    oh how about if we have something like this -2x=-6 then we just solve for x. Because what I am assuming is that the last entry in A and B are supposed to be equal.

  7. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    I have done these, but with 2x2 or above

  8. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I could give you the possible answers if that would help?

  9. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    a. x = -5.7 b. x = -17.7 c. x = 7 d. x = 6

  10. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yes please

  11. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    what the O_O!

  12. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Yeah...my reaction exactly.

  13. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    this is so weird.. I'm calling wolfram lol

  14. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    lol okay. That's a good idea. This was the original problem... \[[-8 -14-2x] - ([-19 +17 -1] + [14 +13 -2]) = [-3 -44 -9]\]

  15. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    T_T wait a sec.. I might have ... did you do the operation in paraenthesis first?

  16. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Oops! Ignore the plus signs. I dunno why I put them inside the matrices. and yes I did. Was I not supposed to?

  17. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    -.- ok hold on I think I might have see what is going.. yes you should do the ones in paraenthesis first ..

  18. Loser66
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Question: how A = B??

  19. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    that's what I was thinking too.

  20. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    what makes A=B ? but when I was to do the problem.. if I let x = 3 that last part will be equal but the first 2 entries aren't equal

  21. Loser66
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    if A = B ,then -8 =2?? -14 =-74 -2x = -6 but how??

  22. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    something is wrong with the arithmetic.

  23. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    let's do it over... and no shortcut cheats.. now this is the original problem right? \[[-8 -14-2x] - ([-19 +17 -1] + [14 +13 -2]) = [-3 -44 -9]\]

  24. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    That wouldn't surprise me. I've been doing math since about 10 am. and yes it is.

  25. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[[-8, -14,-2x] - ([-19 , 17 , -1] + [14, 13 ,-2]) = [-3, -44, -9]\]

  26. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    let me put on my cglasses

  27. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    now let's do the ones in the () with adding the matrices.

  28. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[- ([-19 , 17 , -1] + [14, 13 ,-2]) \]

  29. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[- ([-19+14 , 17+13 , -1-2] )\]\[-[-5,30,-3] \rightarrow [5,-30,3]\]

  30. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[[-8 -14-2x] - [5, -30, 3] \rightarrow [-8-5-14-(-30),-2x-3]\] are you sure it's not [8, -14, 2x] ?

  31. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[[8 -14-2x] - [5, -30, 3] \rightarrow [8-5-14-(-30),-2x-3] \rightarrow [3, 14+30,-2x-3] \rightarrow [3, 44, -2x-3\] \[ \rightarrow [3, 14+30,-2x-3] \rightarrow [3, 44, -2x-3]\]

  32. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yay I think I got what x is !

  33. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    on the last entry we have to solve for x so now we have \[ [3, 44, -2x-3] = [3, 44, 9]\]

  34. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Really? (sorry, I'm doing this an something else at the same time)

  35. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    wait a sec... I think there are typos

  36. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    I think.. let me do this on paper.. there is a typo somewhere on your end or something.

  37. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Okay.

  38. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    -_- I got x = 3. who are these people giving these choices anyway?

  39. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[[-8, -14, 2x] +[ 5 -30 ,3] = [-8+5, -14-30, 2x+3] = [-3, -44, 2x+3]\]

  40. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    It's just random questions I'm given for practice. At the moment, I am unable to view the question, but as soon as I can, I'll let you know if there were any typos in my copy.

  41. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[[-3, -44, 2x+3] = [-3, -44, -9]\] there could be typos on my end but I got it... ok THIS TIME I AM CERTAIN I GOT IT!

  42. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    we just have to focus on the last equation because our first two entries are equal so we now solve for x for that last entry 2x+3=-9 2x =-9-3 2x=-12 x =- 6 there's a typo in your multiple choice

  43. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yup x = -6 \[[-3, -44, 2(-6)+3] = [-3, -44, -12+3] = [-3, -44, -9]\]

  44. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    yay finally it's over. can I get a medal for this 1 x 3 horror festival? I'm not use to adding and solving like that XD

  45. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    -2x+3 = -9 doh I dropped a sign. It's D -2x = -9-3 -2x=-12 x=6

  46. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    You're awesome! :D Hopefully I'll never get another question like this again, but thank you so much for all your help.

  47. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    that question sucked... I was never given like this and I'm used to adding vertically!

  48. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Honestly, I've never had one like this either. The moment I looked at it, my brain went blank.

  49. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    it was tedious. doable but tedious... I think the latex threw me off too. That's why I got so many answers and what not.

  50. UsukiDoll
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Cleaned up version \[[-8 -14-2x] - ([-19 +17 -1] + [14 +13 -2]) = [-3 -44 -9]\] \[\[[-8 -14-2x] - ([-19+14 , 17+13 , -1-2] ) = [-3 -44 -9]\] \[\[[-8 -14-2x] - ([-5, 30 , -3] ) = [-3 -44 -9]\] \[\[[-8 -14-2x] +([5, -30 , 3] ) = [-3 -44 -9]\] \[\[[-8+5, -14-30,-2x+3] ) = [-3 -44 -9]\] \[\[[-3, -44,-2x+3] ) = [-3 -44 -9]\] \[-2x+3=-9 \] \[-2x+3-3=-9-3 \] \[-2x=-12 \] \[\frac{-2x}{-2}=\frac{-12}{-2}\] \[x=6\] \[\[[-3, -44,-2(6)+3] ) = [-3 -44 -9]\] \[\[[-3, -44,-12+3] ) = [-3 -44 -9]\] \[\[[-3, -44,-9] ) = [-3 -44 -9]\]

  51. 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.