Thread: Direct variation help

Can some answer these for me please?

Do the following equations represent direct variations? If so, find the constant of variation

1. 3x-4y=9
2. y=1/5y
3. 8x=4y




thanks

please .

two variables, y and x, are in a direct variation if y and x can be written in the form y = kx , where k is any constant.

Originally Posted by ssppsabres

please .

Please do not "bump" your thread. See rule #1 here.

-Dan

can u answer the question for me tho? Please

Look at the first equation. Solve it for y. Is this in the form y = kx? Use the same method for the other two. Post your solution for #1 (or either of the others) so we can see if you err at some point.

-Dan

y=1.5?

Originally Posted by ssppsabres

y=1.5?

how did you get that from the equation 3x - 4y = 9 ?

y=3?

Originally Posted by ssppsabres

y=3?

no. you are guessing.







or



now ... is this equation in the form ?

No, so therefore it is not a DV and has no constant?

So no its not?

Please post complete sentences and show your work.

Question #1 asked "Do the following equations represent direct variations? If so, find the constant of variation
1. 3x-4y=9"
and when asked to post your solution, you posted, in three separate posts,
"y=1.5? "

"y=3? "

"So no its not?"

The first two make no sense because you were not asked to find a value of y. The last makes no sense because it is not a complete sentence- "so no its not" what?

Since the questions asks, first whether or not the relation given is a "direct variation", you should start by stating what a direct variatio is and then show how the given relation does or does not satisfy that. If it is a direct variation, then you should give the constant of variation, which is NOT "y".