En un estacionamiento hay 55 vehículos entre coches y motos. Si el total de ruedas es de 170. Cuantos coches y cuantas motos hay?

Let [tex]x[/tex] be the number of cars (coches) and [tex]y[/tex] the number of motorbikes (motos).
We know that sum of cars and motorbikes is 55, so:
[tex]x+y=55[/tex] equation (1)
We can infer that the a car has 4 wheels and a motorbike has 2 wheels.Since the total number of wheels is 170, the sum of the car's wheels and the motorbike's wheels is 170:
[tex]4x+2y=170[/tex] equation (2)

Solving for [tex]x[/tex] in equation (1):
[tex]x+y=55[/tex]
[tex]x=55-y[/tex] equation (3)

Replacing equation (3) in equation (2):
[tex]4x+2y=170[/tex]
[tex]4(55-y)+2y=170[/tex]
[tex]220-4y+2y=170[/tex]
[tex]-2y=-50[/tex]
[tex]y= \frac{-50}{-2} [/tex]
[tex]y=25[/tex] equation (4)

Replacing equation (4) in equation (3):
[tex]x=55-y[/tex]
[tex]x=55-25[/tex]
[tex]x=30[/tex]

We can conclude that there are 30 cars and 25 motorbikes in the parking lot.
Podemos concluir que hay 30 coches y 25 motos en el estacionamiento.