Question

PLEASE!!! Will give medals. Can someone explain to me the direct variation concept. How to find a value f y with a given value of x.

Answer 1

Direct variation means your output value, y, varies with your input value, x, such that they are directly proportional.

So as one decreases, the other will decrease and vice versa.

Basically, it's a line on a graph.

f(x) = kx, k cannot be 0, there it's just a horizontal line when y = 0.
y = kx

Answer 2

Depending on your "k" value, your output will change differently with every input value of x.

Answer 3

"k" can also be considered your slope, since we're dealing with lines.

Answer 4

Thank you! If its not too much can you help me answer a question?

Answer 5

Sure. Shoot.

Answer 6

Find the value of y for a given value of x, if y varies directly with x. If y = 3.3 when x = 1.65, what is y when x = 4.85?

Answer 7

On this problem I'm not to sure what the constant K is.

Answer 8

Well you know the formula for direct variation:
y=kx

You've been given a y-value and an x-value.

Answer 9

so I'm assuming the k is the y?

Answer 10

So you know that when:
y=kx
3.3=k(1.65)

What is k?

Answer 11

No, you're not making any assumptions here.

Answer 12

okay, now I get it. But there's still one issue. How do I find the K?

Answer 13

Haha, well you're given y, x and your only unknown variable is k.
You can solve for it! :D

Answer 14

I divide both sides by 1.65?

Answer 15

Yeah. :D

Answer 16

Thank you soooo much! Do you go to connectionsacademy?

Answer 17

my answer is 2, and 2 is not one of the answer choices.

Answer 18

Your k-value is 2. The question isn't asking for the k-value, it's asking for:
the value of y when x=4.85

Answer 19

Now that you have your k-value, you can use it to find y when x is 4.85.

Answer 20

okay thanks!

Answer 21

:) welcome!