Which of the following is the set of real numbers that are 4 units from 7?
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Answer:
see below
Step-by-step explanation:
The difference of 7 and x is 7-x. The difference of x and 7 is x -7. If you want the positive difference regardless of which (7 or x) is larger, you can make the difference be positive by using the absolute value: |x -7|.
We want numbers such that this difference is 4, so we want the solutions to ...
|x-7| = 4