Question

What are the solutions boundaries to `abs(x-10)<1`?

Answer 1

`|x-10|` is always non-negative.

Explanation:

So the lowest value is `0`
The highest value is `1`, as given, so:
`0<=|x-10|<1`

These belong to `x`-values of
`10<=x<11` and `9 < x <=10`
Since these are adjacent the answer is `9 < x<11`
graph{|x-10| [-0.44, 15.36, -1.35, 6.55]}