Help plz I don’t remember the right one

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

This graph shows which inequality? a ≤ –3 a > –3 a ≥ –3 a < –3

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?