Which ordered pair is a solution to the system of equations below? x − y = 2 y = 2x − 4

During a bike challenge riders have to collect various colored ribbons each 1/2 mile they collect a red ribbon each eighth mile they collect a green ribbon and each quarter mile they collect a blue ribbion wich colors of ribion will be collected at the 3/4 markrer

Ineed me i stuck and i don’t want to get it wrong

Which expression is rational? 6. , square root two, square root 14, square root 49