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:
B is the only number that is divisible by 3
Answer:
a=2, b=5
Step-by-step explanation:
Let
n -----> the denominator
we have

Solve for n
That means -----> isolate the variable n
Multiply by n both sides

Divide by 3.5*10^4 both sides

therefore
a=2, b=5
Answer:
y = 1/2x +6
Step-by-step explanation:
We have a point and a slope. Therefore we can use the point slope form to create a line
y-y1 = m(x-x1)
y-5 = 1/2(x--2)
y-5 = 1/2(x+2)
Distribute the 1/2
y-5 = 1/2x +1
Add 5 to each side
y-5+5 = 1/2x +1+5
y = 1/2x +6
This is in slope intercept form