Hey. Let me help you on this one.
In order for us to solve this question, we need to know how these variables work within the problem. There are many ways of solving this problem; however, we will solve this logically by using both order of operations, and simplification of the problem.
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Let's look at the first one.
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can be simplified and made into (15)x. We got this expression by adding 12 and 3.
Now, let's review the second one
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can be simplified into (15x)x, and the latter one can be simplified by multiplying two unknowns together to make 15x^2 (it is squared since we have multiplied two exact numbers together)
The second one is not similar to the first one, and we need at least three to know which one of them is not equivalent to the rest.
The third expression is
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, which is a simplified version of the first one. This shows us that the second statement is not similar to the rest.
Fourth one is
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, and it can be simplified by adding 12x and 3x together, giving us 15x. This one is similar to other two expressions.
After simplifying each and other one, we now know which one is not equivalent to others - second option
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.
Answer:
is not equivalent to other expressions.