He walked 5 miles.
[tex]5x+60y=35[/tex]
[tex]x+y=1.5[/tex]
Solutions (via elimination or substitution) are:
[tex]x=1[/tex]
[tex]y=.5[/tex]
x is the number of hours he spent walking, and 5x is the number of miles he walked. [tex]5x=5(1)=5[/tex] . He walked for 5 miles.
y is the number of hours he spent on the bus, and 60y is the number of miles he rode on the bus. [tex]60y=60(.5)=30[/tex] . He rode the bus for 30 miles.