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 :)
Besides using the word "every" before the singular forms of the words above, they can also be changed to their plural forms by adding "s" behind them. For example "morning" becomes "mornings".
<h3>
Plural form of Morning in a Sentence</h3>
- He works mornings. or
- Mornings, I like to exercise.
Other examples related to the words above are:
- The Tuesdays in March are going to be very busy.
- The nights I spent on the voyage was blissful.
See the link below for more about the Plural forms:
brainly.com/question/586494
Given:
The given expression is

To find:
The two other equivalent expressions.
Solution:
We have,

Using distributive property, we get


So, one equivalent expression is
.
On further simplification, we get


Therefore, the second and fully simplified equivalent expression is
.
Just put the numbers under one square root symbol and try to simplify.
The total number of possible fivey sequences are; 6
<h3>How to solve a sequence?</h3>
We are told we are dealing with a fivey sequence which means that all the terms of the sequence must be positive integers and they must add up to 5.
Now, the possible numbers that can be used are;
1, 2 and 3.
If we start with 3, number of possible sequences is; 1
If we start with1, number of possible sequences is; 3 ways
If we start with 2, number of possible sequences is; 2 ways
Thus;
Total number of fivey sequences is 1 + 2 + 3 = 6 possible sequences
Read more about Sequence at; brainly.com/question/13612968
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