Im confused and need to get my late work in asap!

Brook states that the distance on the line is 4 units. caleb states that the whole line does not have a distance because it continues on forever. vivian states that the line is 6 units long. which distance did brook measure? which distance did vivian measure?

Ineed ! the person who answers and shows their work on they got the answer first will be marked the !

Find the roots of the equation below. x^2 - 6 + 9 = 0