Solve this by substitution :
5x-y =5
5x-3y=15

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

Solve this problem! extra ! 3025/5.5 = a/90.75

Iknow its nothing to do with education, but what type of thing should i wrote here? ? : ) its for mcdonald's btw.