What is the ordered pair of 2x-y=-1

With number 11 ( show how you got the answer)

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?

The function below is written in vertex form or intercept form. rewrite them in standard form and show your work. y = 5(x+3)^2-4