Find the slope of the following 2 points (2,-5), (9,3)

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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?

Vinny is interviewing for a job.he wants his take home pay to be at least $42,000.what is the least salary he can earn if he pays 25% income tax?