Which is the best approximation for 60 squared feet

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning

Find the domain of the following expression: 1/(√x)-2

Ineed to know the ordered pairs for this equation i need the answer quick because it’s a timed test