In which of the following systems can elimination be used to eliminate a variable by performing addition only? 2x – y = 8 x – 2y = 9 2x – y = 8 x – 2y = 9 2x – 4y = –2 5x – 2y = –2 2x + y = 8 3x – y = 4

Onstruct the grouped frequency table for the following data. 1, 1, 1, 1, 2, 2, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9

Which scenario describes intraspecific, indirect competition? a. a peacock defends its territory against another peacock. b. lions and hyenas compete for the same prey animals. c. a male black bear eats fish in an area of a lake, so other black bears can’t. d. different species of birds fight over spilled popcorn on the ground.

Case # 51173878 weighs 814 pounds; case # 51173981 weighs 803 pounds; case # 51174058 weighs 817 pounds; case 51174178 weighs 815 pounds; case # 51174248 weighs 817 pounds; case # 51174495 weighs 781 pounds; case # 51174577 weighs 828 pounds. what are the case #'s of the two cases that weigh the same amount?