Answer: 4
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Step-by-step explanation:
We can pick any (x,y) point on this blue line as long as we don't pick (0,0)
This is because we cannot divide by zero.
Let's say we pick the point (x,y) = (1,4)
The constant of proportionality is found like so
k = y/x
k = 4/1
k = 4
The constant of proportionality is 4
Or we could pick a point like (2,8) to get
k = y/x
k = 8/2
k = 4
We get the same thing.
There are infinitely many points to pick, but in my opinion, it's easiest to stick with (1,4).
As a slight alternative, you can apply the slope formula (pick any two points you want on the blue line) and you should get 4 as well.
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Extra info:
- The direct proportion equation always goes through the origin. This means the y intercept is 0.
- The slope is equal to the constant of proportionality.
- The equation of this line is y = 4x