The answer will be narrow
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:
1/4
Step-by-step explanation:
Answer:
a = 2
b = 5
Step-by-step explanation:
Given :
(ar^b)^4 = 16r^20 ; a and b are positive integers :
Opening the bracket :
a^4r^4b = 16r^20
a^4 = 16 - - - - - (1)
r^4b = r^20 - - - (2)
a^4 = 16
Take the 4th root of both sides :
(a^4)^(1/4) = 16^1/4
a = 2
From (2)
r^4b = r^20
4b = 20
Divide both sides by 4
4b/4 = 20/4
b = 5
Hence ;
a = 2
b = 5
It should be C
The sequence goes 2, 7, 17, 37
2 * 2 = 4 + 3 = 7
7 * 2 = 14 + 3 =17
17 * 2 = 34 + 3 =37
and so on.
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