write an equation that you can plug in any amount of money.
x = .50y + 1.50
.50 comes from the 50 cents per mile. the miles are y, since the price changes depending on how far she travels.
you add 1.50 because no matter what, you have to pay 1.50, even if you got in and went 0 miles.
x will be the 25 dollars max she can spend
25.00 = .50y +1.50 you want to isolate the y
so subtract 1.50 from each side
23.50 = .50y now divide .50 from each side
47 = y
the answer is 47 miles.
you can check this answer by plugging in 47 in the equation.
