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:
Answer:
568 pens.
Step-by-step explanation:
Total number of pens bought = 14 * 50 = 700.
Total pens taken by the workers = 33 * 4 = 132.
Number left = 700 - 132 = 568.
Sq of 196 is 14 then x2 = 28 then 25= 5
You need to have variables one one side and constants on the other. ax - ax + by = c - ax
by = c - ax
by/b = (c - ax)/b
y = (c - ax)/b
Answer:
Choice A
Step-by-step explanation:
5 red socks, 2 white socks, 3 blue socks = 10 socks
1 st sock red : 5 / 10
2nd sock red : 4/9
we didn't put the sock back
a pair of red socks
5/10 * 4/9 = 20/90 = 2/9