55 I hope this helps you!
I think you would do this first add 3.50+1.75=5.25 ( amount she spent so far)
5.25+2x <= 24.50 solve the equation
first, subtract 5.25 from both sides then you get 2x=24.50 then x=12.25 so about 12 rides
(-5,1) because y=x mean that you have to switch the numbers
