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Expression value intuition

In an expression like 2x+7, the value of x can change. As the variable increases and decreases, what happens to the value of the expression?
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Expression value intuitionSee video transcript

Make sure you understand the question that Sal solved.

What happens to the value of the expression 100, minus, x as x increases?
Choose 1 answer:
Choose 1 answer:

Let's try some practice problems!

Question 1
What happens to the value of the expression k, plus, 35 as k decreases?
Choose 1 answer:
Choose 1 answer:

Want to join the conversation?

  • winston default style avatar for user Chrisean Williams
    Can any of you guys can help me with this? I am really struggling with this topic. Please help...
    (6 votes)
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    • leaf grey style avatar for user Mageborn
      What part of it do you not understand? If it's all of it, you should probably go to previous lessons, and study a bit more. If there's a particular section you don't understand, or a part where it gets confusing, then we can better help you.
      (1 vote)
  • winston baby style avatar for user gc515226
    Why does it stay the same? It would decrease because it's a division problem. How does it stay the same?
    (4 votes)
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  • blobby green style avatar for user Farhan Riaz
    Hi guys, I just wanted to understand the goal of this particular lesson...

    I am in no way trying to be cynical, but, serious

    What's the point of this?
    Do we memorise this?
    i.e.
    "When you are subtracting a variable that it is Increasing, the expression Decreases"
    "When you are dividing by a variable that decreases but still remains a whole number, the expression Increases"
    "When you are dividing an increasing variable by itself, as long as it is a whole number, regardless of the value of the Variable, the answer will always be the coefficient divided by the coefficient" - in which case the usage of the variable becomes obsolete.

    Please explain,

    Thank You
    (5 votes)
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  • blobby green style avatar for user Belinda Cozier-fingal
    i still don"t understand the concept. Hope someone can help me simplify it to my understanding
    (3 votes)
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  • blobby green style avatar for user ayuami0001
    it hard but not that much
    (3 votes)
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  • blobby green style avatar for user M McNeal
    The video says, and the table shows, that the last problem would stay the same, yet the system markd this response as incorrect. It says that 2(t/t) decreases. Does anyone know why?
    (3 votes)
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  • blobby green style avatar for user Martin Roy
    This makes no logical sense. If k=1 then 1+35=36, If k=2 then 2+35=37. both numbers are increasing. Yet the right answer is that it decreases. The explanation isn't really an explanation but a string of numbers. How could these numbers be decreasing? The second expression of the exercise says it decreases also but yet the expression is now 30-3a. I find there's no pattern regardless if the expression is addition or subtraction.
    (3 votes)
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    • blobby green style avatar for user Sivakami Pai
      I believe you are getting confused. The question is asking what will happen to k or a when their values are changed. Number k’s value is decreasing, so the overall sum is going to get smaller. Number a is a little different though, because now we are increasing the value of the subtrahend (the number that is subtracting the minuend), so the value will decrease. The questions are a little confusing so you might need to understand what exactly the question is telling you.
      (1 vote)
  • mr pants pink style avatar for user amelianetherland
    i neeed help also because i have no idea if it increases or decreses
    (2 votes)
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  • blobby green style avatar for user 2029fulls79
    Me neither. I mean, I get the concept but it is just little confusing.
    (2 votes)
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  • duskpin seedling style avatar for user Layla Green
    How come it stays the same?
    (1 vote)
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