Answer:
Nathan rode his bike [tex]2\ miles[/tex]
Step-by-step explanation:
Let
x-----> number of miles that Miguel rode his bike
y-----> number of miles that Nathan rode his bike
we know that
[tex]x=5y-4[/tex] -----> equation A
[tex]x=6\ mi[/tex] -----> equation B
equate equation A and equation B and solve for y
[tex]6=5y-4[/tex]
[tex]5y=6+4[/tex]
[tex]5y=10[/tex]
[tex]y=2\ mi[/tex]