Answer: x - 4 without the absolute value bars surrounding it
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Explanation:
If x is larger than 4, then x-4 is positive. For example, if x = 5, then
x-4 = 5-4 = 1
So for cases when x > 4, the |x-4| and x-4 are the same identical expression. Try out more values of x to compare the two outputs. I recommend making a table with 3 columns. You'll have x in column 1, then |x-4| in column 2, and x-4 in column 3. You should find that the outputs for columns 2 and 3 are identical when x is larger than 4.
It's only when x < 4 is when |x-4| and x-4 differ. Instead we would say |x-4| = -(x-4). But we aren't focused on this case.
In short, when x > 4, we simply drop the absolute value bars to get the answer x - 4
