If the sum of two non-negative number X and it's square is less than 12 then what are the possible value of x​

Triangle xyz has vertices x(1,3), y(0,0)

What is the measure of angle tvu shown in the diagram below

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?