the correct question is
A triangle has side lengths of 7 centimeters, 5 centimeters, and c centimeters. enter a value to complete the inequality that describes the possible values for c, the length of the third side of the triangle.
we know that
The sum of the lengths of any two sides of a triangle must be greater than the third side
If c is the smallest number, then
5 + c > 7
c > 2
If c is the largest number, then
5+7 > c
12 > c----------> c < 12
the answer is
The value of c must be in the interval (2,12)