B = {v | v is less than or equal to 1} B has this number line graph: <===============☻--------------------------------- -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 C = {v | v is less than 9} C has this number line graph: <=======================================o--------- -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 To find B∪C put them together and include everything that is in one set or the other or both: <===============☻ <=======================================o--------- -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 All of B is included in C, so the answer is just the same as C, and the interval notation isNotice the parenthesis ")" on the right because 9 is NOT included.] To find B∩C put ONLY include everything that is in both sets: <===============☻ <=======================================o--------- -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 We cannot include the interval from 1 to 9 because it is not in BOTH sets. All of C is included in B, so the answer is just the same as B, and the interval notation is: Notice the bracket "]" on the right because 1 IS included.] Edwin