Answer:
c. 1 and 13
Step-by-step explanation:
If we know two sides of a triangle, a and b, the third side c must be between a + b and a - b, so:
a - b < c < a + b
Therefore, the side withe length x + 3 can be between the following values:
10 - 6 < x + 3 < 10 + 6
4 < x + 3 < 16
Then, we can solve for x, so:
4 - 3 < x + 3 - 3 < 16 - 3
1 < x < 13
So, x is a number between 1 and 13.