The solution set x ≤ 2 or x ≥ 4 is consistent with an equation of the form

The solution includes values outside the interval from 2 to 4, so it has the form of an absolute value being greater than or equal to a positive number. For example, |x − 3| ≥ 1 gives x ≤ 2 or x ≥ 4. Thus the matching form is |ax + b| ≥ c, where c is greater than zero.

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