Can someone explain this? ?

b) determine the first value of the arithmetic sequence in
which t70 = 500 and d = -43.

Plz heeeeeeelp plz give me the answer

The lengths of two sides of a right triangle are given. find the length of the third side. round to the nearest tenth if necessary. a) y = 12/5x + 39/5 b) y = 5/12x + 5/39 c) y = 12/5x - 39/5 d) y = 5/12x - 5/39

Laura read 1/8 of a comic book in 2 days. she reads the same number of pages every day. what part of the book does she read in a week