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6th grade
Unit 6: Lesson 6
Expression value intuitionExpression 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?
Make sure you understand the question that Sal solved.
Let's try some practice problems!
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Can any of you guys can help me with this? I am really struggling with this topic. Please help...(6 votes)
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)
Why does it stay the same? It would decrease because it's a division problem. How does it stay the same?(4 votes)
2t divided by t is the same as 2 - the t on top and bottom can 'cancel' each other out (as they'll grow at the same rate).
It's a tricky one and will become more apparent as you go further through the Algebra syllabus here!(3 votes)
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)
It gets you thinking about numbers, variables and their relationship. As you go further into the algebra playlist, it becomes apparent.(2 votes)
- i still don"t understand the concept. Hope someone can help me simplify it to my understanding(3 votes)
- it hard but not that much(3 votes)
- 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)
I just tried it. I selected "stays the same" and it was marked correct.(2 votes)
- 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)
- 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)
i neeed help also because i have no idea if it increases or decreses(2 votes)- Me neither. I mean, I get the concept but it is just little confusing.(2 votes)
How come it stays the same?(1 vote)
2t/t is the same as 2/1 * t/t. No matter what t is, the ratio is the same i.e. 2.
ex1: t=5 - 2/1 * 5/5 = 10/5 which simplifies to 2/1 which is 2.
ex2: t=10 - 2/1 * 10/10 = 20/10 which simplifies to 2/1 which is 2.(1 vote)