Find the sum and the difference of the following expressions: a+b and a–b

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?

What is the value of x in the diagram below?

Jordan got 27 out of 90 correct on his test . what fraction of the marks did her get correct