A polygon has the following coordinates: A(-6,5), B(-1,5), C(5,3), D(-1,1), E(-6,1). Find the length of DE.

Find the number of positive three-digit even integers whose digits are among 9, 8, 7,5, 3, and 1.

He that is measured at 220° is a reflex angle. the opposite angle is obtuse. find the measure of obtuse .

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning