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 :)
236
2 hundreds + 3 tens + 6 ones or
200 + 30 + 6
236
Answer: Choice A) 
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Work Shown:


When going from 234 to 9*26, the idea here is to factor where one factor is the largest perfect square possible. That way we can use the rule
to break up the root and simplify.