Question

Each month, Kaisorn deposits $50.00 onto her public transportation card. It costs her $2.50 per trip to ride the subway. Thom deposits $40.00 on his public transportation card. It costs him $2.00 per trip to ride the subway.

Answer 1

For this case, the first thing we must do is define variables.

We have then:

x: number of trips.

y: amount of money remaining.

We now write the equation for each person.

For Kaisorn we have:

$y = -2.50x + 50$

Pata Thom we have:

$y = -2x + 40$

Answer:

The system of equations that represents this situation is given by:

$y = -2.50x + 50$

$y = -2x + 40$

Answer 2

If x represents the number of trips and y represents the amount remaining in each account,
50 − 2.5x = y
40 − 2x = y