To create the expression for the total cost of the car washes, we'll consider both the one-time fee and the cost per car wash. The total cost
Where:
is the one-time fee, is the cost per car wash, and is the number of car washes purchased.
Now, to find the total cost for 10 washes, we will substitute
So, the expression to fill in is:
Response area for the expression: 5 + 14w
And the total cost for 10 washes:
Response area: $145