Answer:
6.5 cm < x < 14.5 cm
Explanation:
The length of the side of a triangle must be greater than the difference of the lengths of the other two sides and less than the sum of the other two sides.
Difference: 10.5 cm - 4 cm = 6.5 cm
Sum: 10.5 cm + 4 cm = 14.5 cm
Answer: 6.5 cm < x < 14.5 cm