Answer: [-13, 37]
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Explanation:
The smallest x value possible is 12-25 = -13
The largest x value possible is 12+25 = 37
It might help to draw out a number line to see this.
x is between -13 and 37, including both endpoints. We can write [tex]-13 \le x \le 37[/tex]
This converts to the interval notation [-13, 37] which is the answer.
The use of square brackets is to indicate "include this endpoint".