In order to find out the number of hours that Dalyn used the boat, you can use the formula, 30 + 10x = 90.
Dalyn rented the boat for $30 and then an additional $10 for every hour which brought his total cost to $90.
Assuming that the hours he used the boat was x, the expression would be:
Total cost = Flat fee + (Amount per hour x Number of hours used)
90 = 30 + (10 × x)
30 + 10x = 90
If you solve this equation, the number of hours would be:
30 + 10x = 90
10x = 90 - 30
x = 60/10
x = 6 hours
In conclusion, you can use the formula, 30 + 10x = 90, to find the number of hours rented.
Find out more at https://brainly.com/question/7852289.
