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jchick

  • one year ago

I need help with making examples I don't know what to do for that. You must create a lesson that teaches another student how to solve the following inequality: –x + 3 > 7. Your main mission for this activity is to provide a detailed answer to the question below. Why must you flip the inequality symbol when you divide by a negative number? You know that if the symbol is not flipped you will end up with a false statement, but why is that so? Research and brainstorm (with your partner if you chose to do this collaboratively) to come up with this answer. Remember, you are teaching this to another student, so you must include detailed explanations, visuals, and at least two additional examples. You may submit your lesson in a word document, power point presentation, use audio/video tools, etc. In order to solve –x + 3 > 7 you would first want to add x to both sides which would give you 3 > 7 + x. Then you would subtract 7 from both sides, doing that should give you the final product of -4 > x. The only thing you want to be careful of is when you multiply or divide by a negative number. However you can avoid this making sure the coefficient of the variable is positive. That is why we added x on the first step. You could have started by subtracting 3 to both sides and getting –x > 4 but then you would have to change the sign to get x so you have to change the inequality as well and ge

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  1. jchick
    • one year ago
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    I just need help coming up with the examples I am not sure what to do for that

  2. jchick
    • one year ago
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    In order to solve –x + 3 > 7 you would first want to add x to both sides which would give you 3 > 7 + x. Then you would subtract 7 from both sides, doing that should give you the final product of -4 > x. The only thing you want to be careful of is when you multiply or divide by a negative number. However you can avoid this making sure the coefficient of the variable is positive. That is why we added x on the first step. You could have started by subtracting 3 to both sides and getting –x > 4 but then you would have to change the sign to get x so you have to change the inequality as well and get x < -4. So the answer is X < -4.

  3. jchick
    • one year ago
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    That is how I would explain it but how should I show examples?

  4. jchick
    • one year ago
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    Wow thank you

  5. anonymous
    • one year ago
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    @k142 That is not a very nice thing to say.

  6. jchick
    • one year ago
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    @k142 you do not have to be a jerk about it I am a student and I am trying to learn

  7. anonymous
    • one year ago
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    I told my opinion about that.

  8. anonymous
    • one year ago
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    Okay, let's start with the inequality –x + 3 > 7

  9. jchick
    • one year ago
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    I came on here for help not for criticism

  10. jchick
    • one year ago
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    Thank you @heretohelpalways

  11. anonymous
    • one year ago
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    instead of getting rid of the x, cancel out the 3 by subtracting 3 from both sides

  12. anonymous
    • one year ago
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    to get −x>4

  13. anonymous
    • one year ago
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    then divide both sides by -1

  14. anonymous
    • one year ago
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    to get x<−4

  15. jchick
    • one year ago
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    Ok hang on a sec

  16. anonymous
    • one year ago
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    you are supposed to get x by itself, instead of getting rid of it

  17. anonymous
    • one year ago
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    let's try another inequality

  18. jchick
    • one year ago
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    In order to solve –x + 3 > 7 you would first want to subtract 3 from both sides which would give you -x > 4. Then you would divide both sides by -1. By doing that should give you the final product of x < -4. The only thing you want to be careful of is when you multiply or divide by a negative number. However you can avoid this making sure the coefficient of the variable is positive. That is why we added x on the first step. You could have started by subtracting 3 to both sides and getting –x > 4 but then you would have to change the sign to get x so you have to change the inequality as well and get x < -4. So the answer is X < -4.

  19. jchick
    • one year ago
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    Am I correct up until adding x on the first step

  20. jchick
    • one year ago
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    The answer is correct though right?

  21. anonymous
    • one year ago
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    this might help: http://math.stackexchange.com/questions/94790/why-do-we-reverse-inequality-sign-when-dividing-by-negative-number

  22. jchick
    • one year ago
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    Wait please help me

  23. anonymous
    • one year ago
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    okay , don't worry.I am still here

  24. jchick
    • one year ago
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    Does that explanation at least look right?

  25. anonymous
    • one year ago
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    Wouldn't adding x to -x cancel out the variable

  26. anonymous
    • one year ago
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    the main question/point is "Why must you flip the inequality symbol when you divide by a negative number?"

  27. jchick
    • one year ago
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    In order to solve –x + 3 > 7 you would first want to subtract 3 from both sides which would give you -x > 4. Then you would divide both sides by -1. By doing that should give you the final product of x < -4. The only thing you want to be careful of is when you multiply or divide by a negative number. However you can avoid this making sure the coefficient of the variable is positive. We started by subtracting 3 from both sides and got –x > 4 then you have to change the sign to get x < -4. So the answer is x < -4.

  28. anonymous
    • one year ago
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    so try answering " Why must you flip the inequality symbol when you divide by a negative number?" Then, explain that question in your paragraph, instead of telling them how to avoid the situation

  29. jchick
    • one year ago
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    Ok so I am confused by what I read?

  30. anonymous
    • one year ago
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    this also might help you understand the question: http://mathforum.org/library/drmath/view/53287.html

  31. jchick
    • one year ago
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    Ok

  32. anonymous
    • one year ago
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    Now I am getting confused. I'll tag some people @Skielerlucas04

  33. anonymous
    • one year ago
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    unless you understand it now?

  34. anonymous
    • one year ago
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    @Michele_Laino

  35. jchick
    • one year ago
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    Multiplying it by -1 is like reversing gravity, so that things fall up, and the heavier object is now pulled more strongly up rather than down. If you do that, the scale will reverse:

  36. jchick
    • one year ago
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    But what about dividing it?

  37. jchick
    • one year ago
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    @heretohelpalways The inequality sign changes because you are switching the signs of the values in the inequality. So you must flip the inequality sign as well. Once all values become negative, that means that negatives are flipped from one side to the other (or abolished, if both sides were negative). If the sign is not flipped, it makes the solution a whole different range of numbers, because it changes the inequality.

  38. anonymous
    • one year ago
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    So now explain that inside of your paragraph while explaining how to solve the inequality

  39. jchick
    • one year ago
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    In order to solve –x + 3 > 7 you would first subtract 3 from both sides which would give you -x > 4. Then you would divide both sides by -1. By doing that should give you the final product of x < -4. The only thing you want to be careful of is when you multiply or divide by a negative number. Multiplying or dividing it by -1 is like reversing gravity, so that things fall up, and the heavier object is now pulled more strongly up rather than down. If you do that, the scale will reverse. The inequality sign changes because you are switching the signs of the values in the inequality. So you must flip the inequality sign as well. Once all values become negative, that means that negatives are flipped from one side to the other (or cancelled out, if both sides were negative). If the sign is not flipped, it makes the solution a whole different range of numbers, because it changes the inequality. However you can avoid this making sure the coefficient of the variable is positive. We started by subtracting 3 from both sides and got –x > 4 then you have to change the sign to get x < -4. So the answer is x < -4.

  40. jchick
    • one year ago
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    How is that?

  41. jchick
    • one year ago
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    But I still lack the examples

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