Answer:

Step-by-step explanation:
Given that, Fixed charge = $16
Per hour charge for renting the bike = $8/hour
To find:
If Matt paid $72 to rent a bike, for how many hours did he rent the bike?
Solution:
Let 't' be the time for which Matt rents the bike.
1 hour charge for the bike rent = $8
't' hour charge for the bike rent = $8 
Total Charge for the bike = Charge for renting the bike for <em>t</em> hours + fixed charge
Let '<em>C</em>' be the total charge, so the equation becomes:

Given that C is $72, we need to find <em>t:</em>
<em />
<em />
<em />
So, he rented the bike for <em>7 hours</em>.
The equation is: 