Talk:2018 AMC 10A Problems/Problem 16

The problem asks for the number of line segments. I agree the segments range from length 21-15, and that there are 2 segments of lengths 16, 17, 18, 19 and 20. But surely there exists only one line segment of length 15? (As any other segment forms a right triangle with hypotenuse > 15). Thus why is it counted twice?