Let
x--------> the number of miles
y--------> the total cost in dollars
we know that
[tex]y=5+0.50x[/tex]
[tex]y\leq 30[/tex]
so
[tex]5+0.50x\leq 30[/tex]
therefore
the answer Part a) is
The linear inequality that represent the situation is
[tex]5+0.50x\leq 30[/tex]
Part b)
Find the solution of the inequality
[tex]5+0.50x\leq 30\\0.50x\leq 30-5\\0.50x \leq 25\\x \leq 50\ miles[/tex]
The greatest number of miles that a customer can travel is [tex]50\ miles[/tex]
therefore
the answer part b) is
The solution of the inequality is
[tex]x \leq 50\ miles[/tex]