A direct variation is a mathematical relationship between two variables that can be expressed by an equation in which one variable is equal to a constant times the other. In other words, a direct variation is where

.
In answer a,

, so it is a direct variation.
In answer c,

, so it is a direct variation.
In answer d,

, so it is a direct variation,
Only answer b is left, which means the answer must be 'b'.
We also know 'b' is the answer because it cannot be expressed as <span>

. Instead, it is expressed as </span>

, which is not the same thing and is therefore not a direct variation.
Hope I helped, and let me know if you have any questions :)
Answer:
$137.82
Step-by-step explanation:
The volume of a hemisphere stone is given by the volume of a half-sphere:
Volume = (2/3) * pi * radius^3
If the diameter is 16 inches, the radius is 16/2 = 8 inches, so the volume is:
Volume = (2/3) * pi * 8^3 = 1072.33 in3
We need a total of 8 stones, so the total volume is:
Total Volume = 8 * 1072.33 = 8578.64 in3
The density of clay is 0.0035 pounds per cubic inch, so the total weight of the 8 stones is:
Weight = Total Volume * density = 8578.63 * 0.0035 = 30.0252 pounds
Finally, if the price of each pound of clay if $4,59, the final price is:
Price = 30.0252 * 4.59 = $137.82
I think it's 1.0650 but I'm not sure.
Answer:
28
Step-by-step explanation:
The interior triangle has a right angle, and one of its corners is 62, so the other angle, which is vertical to x, is 180-(90+62)=28, so x=28.
Answer:
C.(-3, -3) and (-3,3)
Step-by-step explanation:
When we have a vertical line the slope is undefined.
That means the x values stay the same
C.(-3, -3) and (-3,3)
This has the same x values
m = (y2-y1)/(x2-x1)
=( 3- -3)/(-3 - -3)
(3+3)/(-3+3)
6/0
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