During strenuous exercise, an athlete can burn 10 calories per minute on a rowing machine, whereas on a stair climber the athlete can burn 11.5 calories per minute. Suppose that in a 60-minute workout an athlete burns 633 calories by using both exercise machines.

1) Identify the correct system of linear equations that models this situation, where X represents the amount of time the athlete spent on the rowing machine and Y represents the amount of time spent on the stair climber. show how you got the answers by your work.

• Total exercise time: (choose A, B,or, C)
A. x+y=633
B. x+y=60
C. 10x+11.5y=60

• Total calories burned:
A. 10x+11.5y=60
B. x+y=633
C. 10x+11.5y=633

2) solve the system of equations (using any method) to determine how much time the athlete spent on each type of workout equipment during the 60 minute workout.

• The athlete spent minutes on the rowing machine.
answer?

• The athlete spent minutes on the stair climber.
answer?