Answer is in the attachment below. If you have any questions about the workings, just leave a comment below.
This simplified is 126x so that is equivalent to this expression
Write the conjugates of them then FOIL both the top and bottom, then factor
Avg. speed Joanna runs: 7.5km/h
how much she runs everyday: 15km
15km/7.5= 2 hours of running time everyday
She leaves at 8:30, comes back at ?
8:30+ 2:00= 10:30
Joanna arrives back at 10:30a.m.