D because its more formal then the other ones.
The exponent tells us how many times to multiply a base to itself. The base is, of course, the thing that's being multiplied. When we use exponents, we call it "raising to a power". The power equals to the exponent, so in our example, x is raised to a power of 4.
Or u can use this but the first one is better
Learning about exponents helps students think about and understand expressions. ... Identify when two expressions are equivalent (i.e., when the two expressions name the same number regardless of which value is substituted into them).
Answer:
Choice (3)
is correct.
Step-by-step explanation:
Given expression is 
Now we need to simplify this and check which of the given choices best match with it.


{using formula
}
{using formula
}


{using formula
}
Hence choice (3)
is correct.
We have: x = 3g + 2
Subtract 2 from the both sides,
x - 2 = 3g + 2 - 2
x - 2 = 3g
Now, Divide 3 from both sides,
(x-2)/3 = 3g/3
g = x-2 / 3
In short, Your Answer would be x-2 /3
Hope this helps!
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