How do I set up this equation?

If Y varies directly as X and Y = 12 when X = 3, find Y when X = 16

If y varies directly with x, then there must be some number "k" such as:

y=k*x
Y = 12 when X = 3...So?
12=k*3
k=12/3
k=4
Since you found k, then you can plug in to find Y.
Y= 4*16
Y= 64

To set up the equation, you need to understand how variables Y and X are related.

When Y varies directly as X, it means that as X increases or decreases, Y will also increase or decrease by the same factor. This relationship can be expressed using the formula:

Y = kX

where "k" is the constant of variation.

To find the value of "k," we can use the given information that Y = 12 when X = 3. Plugging these values into the equation, we have:

12 = k * 3

To solve for "k," divide both sides of the equation by 3:

k = 12/3

k = 4

Now that we have the constant of variation, we can use it to find Y when X = 16.

Substitute the known values into the equation:

Y = kX
Y = 4 * 16
Y = 64

Therefore, when X = 16, Y will be equal to 64.