9514 1404 393
Answer:
2 < x < 15
Step-by-step explanation:
The triangle inequality requires all of ...
(x +11) +(2x +10) > (5x -9) ⇒ 30 > 2x
(2x +10) +(5x -9) > (x +11) ⇒ 6x > 10
(5x -9) +(x +11) > (2x +10) ⇒ 4x > 8
The solutions to these are ...
x < 15
x > 5/3
x > 2
So, the final requirement that has x satisfying all of these is ...
2 < x < 15