I really im in need of help

If y varies directly as x2 and y=6 when x=6, find the constant of variation.

James is playing his favorite game at the arcade. after playing the game 3 times, he has 8 tokens remaining. he initially had 20 tokens, and the game costs the same number of tokens each time. the number t of tokens james has is a function of g, the number of games he plays. write the function’s formula? t=

Which radical expression is a rational number? a. √ 360 b. √ 644 c. √ 225 d. √ 122