Inequality Theorem - A problem

Triangle ABC has lengths a = 3 and b = 4. What is the range of values that length c can have?

Answer: By the Inequality Theorem: b + a > c and b - a < c so c > 4 - 3 > 1 and c < 4 + 3 < 7 1 < c < 7 Length of c is between 1 and 7