Question

What is the 19th term in sequence -1,-5,-9,...

Answer 1

The sequence starts at -1 and counts backwards by 4s, so we can find the nth number in the sequence by evaluating the expression -1 - 4n for any number n. Here, we want to find the 19th term, so we set n = 19 and find it to be -1 - 4(19) = -1 - 76 = -77

Answer 2

This is so easy, the answer is -85