Answer:
(a) x = -2y
(c) 3x - 2y = 0
Step-by-step explanation:
You can tell if an equation is a direct variation equation if it can be written in the format y = kx.
Note that there is no addition and subtraction in this equation.
Let's put these equations in the form y = kx.
(a) x = -2y
- y = x/-2 → y = -1/2x
- This is equivalent to multiplying x by -1/2, so this is an example of direct variation.
(b) x + 2y = 12
- 2y = 12 - x
- y = 6 - 1/2x
- This is not in the form y = kx since we are adding 6 to -1/2x. Therefore, this is <u>NOT</u> an example of direct variation.
(c) 3x - 2y = 0
- -2y = -3x
- y = 3/2x
- This follows the format of y = kx, so it is an example of direct variation.
(d) 5x² + y = 0
- y = -5x²
- This is not in the form of y = kx, so it is <u>NOT</u> an example of direct variation.
(e) y = 0.3x + 1.6
- 1.6 is being added to 0.3x, so it is <u>NOT</u> an example of direct variation.
(f) y - 2 = x
- y = x + 2
- 2 is being added to x, so it is <u>NOT</u> an example of direct variation.
The following equations are examples of direct variation:
<h3>
Answer: Choice C</h3>
Explanation:
As the person spends more time raking, the number of leaves will go down. Therefore, we have a negative correlation. Such correlations occur when one variable goes up while the other goes down (and vice versa).
The reason why it's considered negative correlation is because the regression line has a negative slope.
This is why choice C is the answer. This assumes that no extra leaves fall on the ground, and we assume that we don't have nearby leaves blow into the yard.
In contrast, something like choice A has both variables go up together. As the temperature rises, so does the ice cream sales. The same goes for choice B. We consider these cases to have positive correlation. Choice D doesn't appear to have any correlation at all. The person's height doesn't have any connection to the number of pets they may have.
The supplement of an obtuse angle is an acute because the angle number for an obtuse angle is any number greater than 90 degrees. So an acute angle is less than 90 degrees. The "supplement" definition is "any number less than 180 degrees."
Hope this helps,
kwrob
Answer:
By plotting in the number in the equation (aka where all the x’s are variables are) and seeing if it works.
Step-by-step explanation:
For example, let’s use the problem:
3x + 4 = 16
if the given number is 4, we fill it in for x-
3 (4) + 4= 16
solve to see if true:
12 + 4 = 16
16 = 16
hence, the given number 4 makes the equation true!
hopes this helps, have a great day :)
