What is an example of direct proportionality?

[sotellme]

directly proportional? can anyone give an example of it?


thanks alot!

 

[Pyrrhus]

y and x are directly proportional, A is a constant.

y = Ax

\frac{y}{x} = A

 

[Sirus]

Right. This is represented as y\propto x.

 

[sotellme]

thanks!

 

[cyby]

Careful. Make sure A is not a positive constant < 1. Otherwise you will get that they are inversely proportional.

 

[sotellme]

Careful. Make sure A is not a positive constant < 1. Otherwise you will get that they are inversely proportional.

hi cyby! what you mean with that? do you mean that A must always be a positve number if not it will be inversely proportional?

 

[quantumdude]

Careful. Make sure A is not a positive constant < 1. Otherwise you will get that they are inversely proportional.

No, that's not true. It's still a direct proportion. y and x are inversely proportional if y=A/x.

 

[cyby]

Uh, you are right. Sorry, was thinking about something else completely.