Put these in order, using brackets and set notation. PLEASE HELP ME I WILL MARK YOU AS A BRAINIEST!!!

0.54, 8/16, 7/16, 0.44

To solve the system of equations below, grace isolated the variable y in the first equation and then substituted into the second equation. what was the resulting equation? 3y=12x x^2/4+y^2/9=1

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

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