72 is what term of the sequence -5, 2, 9,.

Find the 13th term of the sequence 1, -2, -5

Without using any real sequencing formulas...

for the first one, the only real sequence is to add 7. (-5) + 7 = 2... +7 = 9...

so it depends on whether -5 is the (0th) term or the (first) term.

For our sake, we'll say it's the (0th) term...

-5 + (7)(whichever term) = answer.

so... for example, the first term is

-5 + (7)(1) = 2

second term is

-5 + (7)(2) = 9

similar with the second question.