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:
the last one
Step-by-step explanation:
1 is 60. 2 is 60. 3 is 24. 4 is 365.25. 5 Is 186282. 6 is 5879000000000 or 5.879 X 10^12.
F(-7) = -7 - 10
f(-7) = -17
Hope I helped!
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