yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Constant of proportionality from graph | 7th grade | Khan Academy


less than 1m read
·Nov 11, 2024

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. 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 0, y is 0. But if I multiply 0 by anything, I'm going to get 0.

But then when x is 1, what is y? When x is 1, y is 3. They mark it right over there. When x is 2, what is y? X is 2, we see that y is 6.

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. 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 3, you get your y.

So the relationship here is y is equal to 3x, so 3 is our constant of proportionality.

More Articles

View All
Why you're always tired
One of the most common problems I hear about nowadays, and I’m sure everyone else does, is this feeling of being chronically tired. Because sometimes it feels like no matter how much sleep you get, you just can’t seem to perk up, feel energetic for most o…
Staying in the Lines | Rocky Mountain Law
Have you had anything to drink at all in the last 24 hours? No. Okay, have you had any drugs or anything at all in the last 24 hours? Okay, what’s your native language that you speak? Uh, Pabi. And you understand English? Yeah, for the most part. Very muc…
The Better Boarding Method Airlines Won't Use
[Inaudible airport announcements] [Grey sighs] What’s the fastest way to board an airplane? I mean, you can’t just throw open the gates like funneling cattle into a chute. That’s not for us. We’re primates, after all! So let’s put our monkey brains to wor…
Deficits and debt | AP Macroeconomics | Khan Academy
Two terms that you’ve likely heard in the context of government spending, budgets, and borrowing are the terms deficit and debt. They can get a little bit confusing because they’re associated with borrowing in budgets and spending, and they both start wit…
Midpoint sums | Accumulation and Riemann sums | AP Calculus AB | Khan Academy
What we want to do in this video is get an understanding of how we can approximate the area under a curve. For the sake of an example, we’ll use the curve ( y = x^2 + 1 ). Let’s think about the area under this curve above the x-axis from ( x = -1 ) to ( …
How Many Photos Have Been Taken?
Hey, Vsauce. Michael here. In 1826, this became the very first photograph ever taken. And in 1992, this became the very first image ever uploaded to the web. But how many photographs have we all taken, altogether, throughout all of history? Well, 1000memo…