Answer:
3 < c < 15
Step-by-step explanation:
If a triangle has sides a, b, and c, one of the following relationships must be true:
[tex]a+b>c\\a+c>b\\b+c>a[/tex]
if a =9 and b=6, then:
[tex]9+6>c\\9+c>6\\6+c>9\\c<15\\c>-3\\c>3[/tex]
Combining those inequalities gives us:
[tex]3<c<15[/tex]
Therefore, the length of the third side could be any value between 3 and 15.