The diagram shows a right angle triangle find the size of x give your answer to 1 decimal place

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

Which of the choices shown could be used to prove that aacp=abcp ?

Extra points! find the missing dimension! need asap