1. find the 25th term of the Arithmetic sequence 21,19,17,15, 2.find the 11th term of the Arithmetic sequence -1,0,1,2,... Answer: 1. -27 2. 9 Solution: 1.) 21, 19, 17, 15, 13, 11, 9, 7, 5, 3, 1, -1, -3, -5, -7, -9, -11, -13, -15, -17, -19, -12, -23, -25, -27 2.) -1, 0,1 ,2, 3, 4, 5, 6, 7, 8, 9