Answer: choice a
Explanation:
The Triangle Inequality Theorem states that the sum of any 2 sides of a triangle must be greater than the measure of the third side. Note: This rule must be satisfied for all 3 conditions of the sides.
so it has to be in between 9 and 5
7+2=9
2+x>7
--> x>5
however, it can't be 5 or 9
Hope this helps! <3