I'm confused in the constant proportionality and the way you set it up

The constant of proportionality is the ratio between two directly proportional quantities. Two quantities are directly proportional when they increase and decrease at the same rate. The constant of proportionality k is given by k=y/x where y and x are two quantities that are directly proportional to each other. Once you know the constant of proportionality you can find an equation representing the directly proportional relationship between x and y, namely y=kx, with your specific k. Hope this helps!

This is so confusing and it makes me very mad

Hey, don't worry. Everyone has their least favorite subjects. If you look at the comment above, they explain how to find it. There is also another equation, but thats for later.

why is school so boring

it’s because its a feature for the matrix

But what if you have a decimal, then how do you apply this method?

You can divide the decimals. In a proportional relationship (line through the origin), the proportionality constant is y/x for any chosen point (x,y) on the graph with x nonzero.

what if you ha 0.5 on and 1 on x how would you write that?

If 0.5=Y, 1=X. This is going to get a bit confusing, but I will say, I typically prefer more cleaner numbers. (On graph paper) 0.5=K1 0.5/1=K 0.5=K. (you divided 0.5/1) Now lets add it back in to see if we're correct. 0.5=0.5(1) 0.5=0.5 (you times 0.5*1) I hope this was helpful!

when can there be no propotion

There is no proportion when x and y are interacting together. For example, when you have a proportion like y=x+2, you will have a straight line on the graph. But when you have something like y=xy, you will get a curved line on the graph which does not fulfill the rule that a proportional relationship should be graphed as a line.

This is a bit confusing I still don’t get it

So, Y (the up and down part of the graph) equals K (The constant of proportionality, you get it by dividing Y by X), times X (the side by side part of the graph.) This would equal= Y=KX Then you look for a clear place where you can place a point, (I would recommend using graph paper for this) say, (4,8) and then you take the Y (X,Y) which is 8 and divide it by the X, which is 4 to get 2. So, K=2. Now lets check it. 8=2(4) 8=8 I hope this was helpful!

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Constant of proportionality from graph

Name: Constant of proportionality from graph
Uploaded: 2018-09-07T17:54:12Z
Description: Sal finds constant of proportionality by looking at the graph of a line.

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Sal finds constant of proportionality by looking at the graph of a line.

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Josmar Jean
Posted 3 years ago. Direct link to Josmar Jean's post “I'm confused in the const...”
I'm confused in the constant proportionality and the way you set it up
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(28 votes)
Answer
- 𝕯𝖎𝖆𝖒𝖔𝖓𝖉 𝕯𝖆𝖗𝖐𝖍𝖊𝖆𝖗𝖙 ⛬ #IgnisaurRules
  Posted 3 years ago. Direct link to 𝕯𝖎𝖆𝖒𝖔𝖓𝖉 𝕯𝖆𝖗𝖐𝖍𝖊𝖆𝖗𝖙 ⛬ #IgnisaurRules's post “The constant of proportio...”
  The constant of proportionality is the ratio between two directly proportional quantities. Two quantities are directly proportional when they increase and decrease at the same rate.
  The constant of proportionality k is given by k=y/x where y and x are two quantities that are directly proportional to each other. Once you know the constant of proportionality you can find an equation representing the directly proportional relationship between x and y, namely y=kx, with your specific k.
  Hope this helps!
  Comment on 𝕯𝖎𝖆𝖒𝖔𝖓𝖉 𝕯𝖆𝖗𝖐𝖍𝖊𝖆𝖗𝖙 ⛬ #IgnisaurRules's post “The constant of proportio...”
  (26 votes)
RickyG
Posted 3 years ago. Direct link to RickyG's post “This is so confusing and ...”
This is so confusing and it makes me very mad
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(25 votes)
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- Inforaptor
  Posted 2 years ago. Direct link to Inforaptor's post “Hey, don't worry. Everyon...”
  Hey, don't worry. Everyone has their least favorite subjects. If you look at the comment above, they explain how to find it. There is also another equation, but thats for later.
  Comment on Inforaptor's post “Hey, don't worry. Everyon...”
  (11 votes)
▓▒░.-.JustPayton.-.░▒▓
Posted 3 years ago. Direct link to ▓▒░.-.JustPayton.-.░▒▓'s post “Am i the only one who loo...”
Am i the only one who looks at the comments lol
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- 27jtran20
  Posted 2 years ago. Direct link to 27jtran20's post “no you are not”
  no you are not
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Hayden
Posted a year ago. Direct link to Hayden's post “why is school so boring”
why is school so boring
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- Mitchell Pacheco
  Posted a year ago. Direct link to Mitchell Pacheco's post “it’s because its a featur...”
  it’s because its a feature for the matrix
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27jtran20
Posted 2 years ago. Direct link to 27jtran20's post “Thanks khan you're better...”
Thanks khan you're better than my math teacher
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Cindy Chen
Posted 3 years ago. Direct link to Cindy Chen's post “This is a bit confusing I...”
This is a bit confusing I still don’t get it
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(4 votes)
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- Zoe baranowski
  Posted 3 years ago. Direct link to Zoe baranowski's post “So, Y (the up and down pa...”
  So, Y (the up and down part of the graph) equals K (The constant of proportionality, you get it by dividing Y by X), times X (the side by side part of the graph.)
  
  This would equal= Y=KX
  
  Then you look for a clear place where you can place a point, (I would recommend using graph paper for this) say, (4,8) and then you take the Y (X,Y) which is 8 and divide it by the X, which is 4 to get 2.
  
  So, K=2.
  
  Now lets check it.
  
  8=2(4)
  8=8
  
  I hope this was helpful!
  Comment on Zoe baranowski's post “So, Y (the up and down pa...”
  (10 votes)
Ahmad Shaheer
Posted 4 years ago. Direct link to Ahmad Shaheer's post “what if you ha 0.5 on and...”
what if you ha 0.5 on and 1 on x how would you write that?
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(5 votes)
Answer
- Zoe baranowski
  Posted 3 years ago. Direct link to Zoe baranowski's post “If 0.5=Y, 1=X. This is g...”
  If 0.5=Y, 1=X.
  
  This is going to get a bit confusing, but I will say, I typically prefer more cleaner numbers. (On graph paper)
  
  0.5=K1
  0.5/1=K
  0.5=K. (you divided 0.5/1)
  
  Now lets add it back in to see if we're correct.
  
  0.5=0.5(1)
  0.5=0.5 (you times 0.5*1)
  
  I hope this was helpful!
  Comment on Zoe baranowski's post “If 0.5=Y, 1=X. This is g...”
  (7 votes)
khalila.danielsdaile
Posted 5 years ago. Direct link to khalila.danielsdaile's post “when can there be no prop...”
when can there be no propotion
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- Czozo
  Posted 3 years ago. Direct link to Czozo's post “There is no proportion wh...”
  There is no proportion when x and y are interacting together.
  For example, when you have a proportion like y=x+2, you will have a straight line on the graph. But when you have something like y=xy, you will get a curved line on the graph which does not fulfill the rule that a proportional relationship should be graphed as a line.
  Comment on Czozo's post “There is no proportion wh...”
  (6 votes)
Caelyn Lavrijsen
Posted 3 years ago. Direct link to Caelyn Lavrijsen's post “But what if you have a de...”
But what if you have a decimal, then how do you apply this method?
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(6 votes)
Answer
- Ian Pulizzotto
  Posted 3 years ago. Direct link to Ian Pulizzotto's post “You can divide the decima...”
  You can divide the decimals. In a proportional relationship (line through the origin), the proportionality constant is y/x for any chosen point (x,y) on the graph with x nonzero.
  Button navigates to signup page
  (4 votes)
TC Deily
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UGG GGG. It won't let me replay the video!
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Video transcript

- [Instructor] The following graph shows a proportional relationship. What is the constant of proportionality between y and x in the graph? Pause this video, and see if you can figure that out. All right, now let's do this together, and let's remind ourselves what a constant of proportionality even is. If we know that there is a proportional relationship between y and x, then there will be a constant of proportionality between these variables, and what this is, is it is a number that I would have to multiply x by to get to y. So I could make a little table here, as we often do when we describe proportional relationships, x and y. We know that when x is zero, y is zero. But if I multiply zero by anything, I'm gonna get zero. But then when x is one, what is y? When x is one, y is three. They mark it right over there. When x is two, what is y? X is two, we see that y is six. So our constant of proportionality is what are we multiplying x by to get to y? Well, let's see, to go from one to three, I have to multiply by three. To go from two to six, I have to multiply by three. Another way to think about it is we could write the equation y is equal to something times x. The number that we multiply x by to get y is our constant of proportionality. And we've seen, in all of these situations, this should be true for any point on this line. You give the x, you multiply it by three, you get your y. So the relationship here is y is equal to three x. So three is our constant of proportionality.

7th grade

Course: 7th grade > Unit 4

Constant of proportionality from graph

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Video transcript