Write an inequality for this expression: all numbers whose absolute value is less than or equal to 15.???

Answer 1

Let x be the numbers... then the expression you want is:
| x | ≤ 15

Note:
This could be expanded to:
x ≤ 15
and
-x ≤ 15 --> x ≥ -15 --> -15 ≤ x

Finally, you can combine these two inequalities:
-15 ≤ x ≤ 15

In other words, any number between -15 and 15 (inclusive) will have an absolute value less than or equal to 15.

Answer 2

|x| <= 15

Answer 3

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