A bill with an entry fee and a price per ride becomes a linear equation: fixed fee plus ride cost equals total. Let the unknown count rides, then enter the finished equation as a Desmos regression to find that count. Add the entry fee once, and multiply only the price that repeats. Multiplying the entry fee by the ride count charges it again on every ride.
Hints
- Hint 1
A rate is the cost of one ride, so multiply it by the number of rides. If counts Sasha’s rides, what expression gives the ride charges?
- Hint 2
The entry fee is paid once, no matter how many rides Sasha takes. Add it to the ride charges, then set that sum equal to what she spent in total.
Step-by-step
Build the bill, then solve in Desmos
Step 1Write the ride charges
Let count Sasha’s rides. The rate is $4 per ride, so the ride charges are dollars.
- Step 2
Write the total-cost equation
The entry fee is a fixed charge: Sasha pays it once, not once per ride. Add , not , to the ride charges and set the sum equal to her $47 total: .
- Step 3
Find the number of rides
Type in Desmos. Use instead of so Desmos finds its value rather than graphing ; tells it to match the two sides. Under PARAMETERS, Desmos shows . Since counts rides, Sasha went on 8 rides. Grid in 8.