Hi!
To find the range of possible values of x, we have to side 1 from side 2...
7.1 - 5.6 = 1.5
The smallest side x could be is 1.5.
Now add side 1 to side 2
7.1 + 5.6 = 12.7
The biggest side x could be is 12.7
So x could be anywhere from 1.5 to 12.7 (or, 1.5 < x < 12.7)
Hope this helps! :)