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fkey3191 Group Title

solving systems of equations by elimination 7x+2y=24 8x+2y=30 explain if possible

  • 2 years ago
  • 2 years ago

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  1. zonazoo Group Title
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    Just multiply the first equation by -1 and add it to the second equation... if it asks you to solve by elimination, it means you need to get rid of a variable in one of the equations...

    • 2 years ago
  2. zonazoo Group Title
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    so your first equations becomes -7x-2y=-24 then add that too the second 8x+2y=30 ... that will then give you 1x = 6 then just substitute back in to either equation to get y

    • 2 years ago
  3. zonazoo Group Title
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    8(6) + 2y = 30 2y = 30 - 48 2y = -18 y = -9

    • 2 years ago
  4. zonazoo Group Title
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    does that make sense?

    • 2 years ago
  5. OrthodoxMan Group Title
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    easy as pie. Use elimination method. 7x + 2y = 24 (1) 8x + 2y = 30 (2) Eliminate (1) and (2) 8x + 2y = 30 - 7x + 2y = 24 ------------------ x = 6 Substitute x = 6 into either (1) or (2) 8(6) + 2y = 30 2y = 30 - 48 y = -18/2 y = -9

    • 2 years ago
  6. OrthodoxMan Group Title
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    you can also check our answers. But with regards to the guy above me, the answer is right.

    • 2 years ago
  7. hba Group Title
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    @zonazoo You have provided the substitution method. @OrthodoxMan Try to interact with the user rather than providing solutions. The easy method to check your answer is to put the x and y values in the original question and check if L.H.S=R.H.S

    • 2 years ago
  8. OrthodoxMan Group Title
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    I get what you mean but some users learn by interpreting the solution rather than following a lesson.

    • 2 years ago
  9. fkey3191 Group Title
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    thank yall (:

    • 2 years ago
  10. fkey3191 Group Title
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    orthodox man helped alot

    • 2 years ago
  11. hba Group Title
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    @OrthodoxMan As a rule of thumb, we would prefer the askers to participate in the solution process instead of having the answerers doing all the work. thats not really our concern; we are aimed at being a study site, not a free answering service. We would rather promote learning the material as opposed to just handing over answers. This social contract is aimed at curbing people from using the site to cheat with ...

    • 2 years ago
  12. zonazoo Group Title
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    and look who gets the best response @hba hahaha

    • 2 years ago
  13. hba Group Title
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    @zonazoo You provided the wrong method. The asker wanted to do it with Elimination method.

    • 2 years ago
  14. whatisthequestion Group Title
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    @OrthodoxMan more than likely when you just type out the solution like that then they just go into a copy and paste format where they are not really thinking about the way it was solved. Also if you are staying with them for the entire question then they should be able to review the conversation just as they are able to review when you post just the solution

    • 2 years ago
  15. zonazoo Group Title
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    @hba and what method are you suggesting I did... b/c what I did was no different than the other.

    • 2 years ago
  16. whatisthequestion Group Title
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    @zonazoo you did elimination which is the same as addition but starts with the subtracting of one equation from the other instead, so you would not say to multiply by -1

    • 2 years ago
  17. OrthodoxMan Group Title
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    You're absolutely right, but this user really doesn't seem like she is doing a test at the moment. More like homework. However, I will keep it in mind for future questions.

    • 2 years ago
  18. OrthodoxMan Group Title
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    Thanks for the warning -.-

    • 2 years ago
  19. Outkast3r09 Group Title
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    lol @hba : this is elimination. Substitution is the other method and that deals with solving for one variable and putting it into the other equation. Medal for @zonazoo

    • 2 years ago
  20. hba Group Title
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    @Outkast3r09 I remember the first method as Substituion and the second as elimination.4 years is a long time dude :)

    • 2 years ago
  21. whatisthequestion Group Title
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    @Outkast3r09 there are three methods for solving a system of equations 1. Substitution 2. Addition 3. Elimination I explained the difference between addition and elimination above

    • 2 years ago
  22. hba Group Title
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    I just checked both the methods and they are same :)

    • 2 years ago
  23. Outkast3r09 Group Title
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    oh i can name many other ways to solve this but the most used are substitution and elimination. In differential equations you solve these using matrices.

    • 2 years ago
  24. whatisthequestion Group Title
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    I know my school system made sre we knew the difference between the two although it is an arbitrary difference

    • 2 years ago
  25. whatisthequestion Group Title
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    I meant at this level if you want to start talk about RREF and graphing and so on we will be here all day listing all the ways to solve this question

    • 2 years ago
  26. hba Group Title
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    @OrthodoxMan Thanks a lot for understanding.

    • 2 years ago
  27. Outkast3r09 Group Title
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    I was talking about using a determinant but RREf works also

    • 2 years ago
  28. zonazoo Group Title
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    addition and elimination are basically the same thing... really the only other basic way to solve these is to graph and find the intersection... other than that you would either just eliminate/add/subtract (whatever you want to call it) or substitute.

    • 2 years ago
  29. Outkast3r09 Group Title
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    and i think i meant linear algebra also hahaha.. differential could find all possibilities lol

    • 2 years ago
  30. zonazoo Group Title
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    and the matrix needs to be a square matrix to take a determinant

    • 2 years ago
  31. OrthodoxMan Group Title
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    Now in regards with my warning, there was no need to give me one. You were already consulting me about this matter that there was no need to take it to issuing me a warning, Warnings are only for obvious mis-behaviours. I have committed none of that..

    • 2 years ago
  32. whatisthequestion Group Title
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    Again I did admit that it always seemed like there wasn't really a difference between the two but I remember them calling them different names based on if we were subtracting or adding the two equations

    • 2 years ago
  33. zonazoo Group Title
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    but either way... i think we have all just taken this topic far beyond what it needs to... im sure we all understand what is said.

    • 2 years ago
  34. fkey3191 Group Title
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    while yall are arguing haha who wants to answer the nest one the same way -4+9y=9 x-3y=-6

    • 2 years ago
  35. hba Group Title
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    @fkey3191 No one is going to answer your question,we can help you though.

    • 2 years ago
  36. whatisthequestion Group Title
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    @fkey3191 I am guessing that is suppose to be -4x + 9y = 9 x - 3y = -6 otherwise that is way to simple

    • 2 years ago
  37. fkey3191 Group Title
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    not for me

    • 2 years ago
  38. whatisthequestion Group Title
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    Okay then do they say it has to be elimination?

    • 2 years ago
  39. OrthodoxMan Group Title
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    Well with respect to my warning, refer to the method I used to solve your previous one and apply your knowledge on solving systems of equations from lessons. Before i get banned, goodluck.

    • 2 years ago
  40. hba Group Title
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    @OrthodoxMan If you have been issued a warning and you feel like you should not be warned,go talk to a mod ( the one in purple ) .

    • 2 years ago
  41. fkey3191 Group Title
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    yess

    • 2 years ago
  42. whatisthequestion Group Title
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    because one equation is already down to one variable which means you could just solve for y and sub in the answer for y into the second to solve for x . . . I do not see how this requires elimination at all.

    • 2 years ago
  43. whatisthequestion Group Title
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    BTW I meant way to simple to use elimination that may not have been clear originally

    • 2 years ago
  44. fkey3191 Group Title
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    okay (:'

    • 2 years ago
  45. whatisthequestion Group Title
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    Well then my last thing to add before leaving is (╯°□°)╯︵ ┻━┻ Why do they want to over complicate things?

    • 2 years ago
  46. fkey3191 Group Title
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    i know he was doing what i needed and i learn by getting the answer then solving up to that soo that guy was wrong.

    • 2 years ago
  47. hba Group Title
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    @fkey3191 If you learnt from the first question,why don't you imply it in the second question ?

    • 2 years ago
  48. fkey3191 Group Title
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    because i have 8 more pages and im not a smarty pants like you...and im not trying to all of them

    • 2 years ago
  49. hba Group Title
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    @fkey3191 I am sorry no one is going to do your homework here.

    • 2 years ago
  50. fkey3191 Group Title
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    take your brain and shove it up your retrice

    • 2 years ago
  51. fkey3191 Group Title
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    butt

    • 2 years ago
  52. hba Group Title
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    @Callisto Please look into the matter.

    • 2 years ago
  53. hba Group Title
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    @fkey3191 Using inappropriate speech is not allowed here,you may be banned to do so. And as i mentioned earlier We are here to help you not provide answers

    • 2 years ago
  54. fkey3191 Group Title
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    i said butt wow

    • 2 years ago
  55. hba Group Title
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    Please read the CoC-http://openstudy.com/code-of-conduct

    • 2 years ago
  56. fkey3191 Group Title
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    bye

    • 2 years ago
  57. fkey3191 Group Title
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    i think you can read it for me

    • 2 years ago
  58. Callisto Group Title
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    For asker, as always, this is a site for learning, not for answer-seeking. So, please do ask the others to do all the work for you (or give you the answer). For the ones who answer the question, we don't encourage you to give answer without the involving the asker in solving the question, since the asker may not learn and just copy your work. That's not learning. Regarding the warning, just take it as an reminder. If you don't make the same mistake again, that'd be fine. Last but the least, please mind the language used here.

    • 2 years ago
  59. Callisto Group Title
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    Oh, I miss one thing there. Please start a new post for a new question.

    • 2 years ago
  60. fkey3191 Group Title
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    thats how i learn but okay.

    • 2 years ago
  61. OrthodoxMan Group Title
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    As i said, not everyone learns the same way. You guys impose quite a strict condition on people who cling to different methods of learning.

    • 2 years ago
  62. Callisto Group Title
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    Hmm.. Perhaps at least the asker can show that he/she has done something but got stuck in somewhere?

    • 2 years ago
  63. OrthodoxMan Group Title
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    Besides, I'm giving a full solution and not just the answer.

    • 2 years ago
  64. hba Group Title
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    There should be some interaction @OrthodoxMan .

    • 2 years ago
  65. OrthodoxMan Group Title
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    As you saw in this example, it clearly did not work. http://openstudy.com/study#/updates/50b1bc5de4b0e906b4a63903

    • 2 years ago
  66. Callisto Group Title
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    The keywords here are ''without the involving the asker in solving the question''

    • 2 years ago
  67. Callisto Group Title
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    In some cases, it might not work, but at least for solving equations, you can let the asker participating in solving the question.

    • 2 years ago
  68. OrthodoxMan Group Title
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    Reword your quote here, it's grammatically incorrect.

    • 2 years ago
  69. Callisto Group Title
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    Sorry, English is not my first language. Excuse me for my poor grammar/English. But do you get the meaning?

    • 2 years ago
  70. OrthodoxMan Group Title
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    Not really, I value the structure of sentences as it allows me to comprehend what you're saying. I would understand your "meaning" through verbal communication. Seems like that won't happen.

    • 2 years ago
  71. hba Group Title
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    '' without involving the asker in solving the question''*

    • 2 years ago
  72. hba Group Title
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    Now it sounds grammatically correct and i hope you understand ?

    • 2 years ago
  73. hba Group Title
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    If you are still having problems , Feel free to post a Question in the Open study feedback group-http://openstudy.com/study#/groups/OpenStudy%20Feedback.

    • 2 years ago
  74. OrthodoxMan Group Title
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    ahh that has been defined countless times in this thread. Now considering the fact I acknowledge who is asking the question and their purpose (say if they are taking a test or exam at the moment), you cannot issue a warning until it has been justified. If my claims are not justified, your goal to turn this site into a study group is not realistic. Why don't you check other threads for a 7 day time span and tell me whether people are giving answers or giving a path of way to the answer.

    • 2 years ago
  75. hba Group Title
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    @OrthodoxMan As i said if you have any further queries please post your questions in the Open study feedback group.

    • 2 years ago
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