I added screenshots with the complete question as well as the available choices.
Answer:25 =

which is the first option
Explanation:We given that:
He charges $100 as enrollment fees and $15 per hour
Given that the number of hours is h, the total cost for h hours will be:
cost = 100 + 15h ...........> I
We are also given that:
The average cost per hour is $25.
This means that:

= $25 ............> II
Divide both sides of equation I by h:

=

Substitute with

= 25 to get the equation used to solve for h as follows:
25 =

Hope this helps :)