The system of equations that represents this situation is:
[tex]t+w=70[/tex]
[tex]20+w=t[/tex]
The first equation is "time spent on the treadmill (t) plus time spent lifting weights equals total time spent working out at the gym (70)". Â The second equation illustrates that the time spent on the treadmill was 20 minutes longer than the time lifting weights.
I hope this explanation makes sense!