Mosfets & Resistance: How Does Vgs = Vds?

[photonxyz]

This isn't a homework question... I'm just trying to understand Mosfets in general. I've been reading about them, and I find them really interesting- very cool. However, I don't understand how the Vgs = Vds if the mosfet itself has resistance!? For example, I found this in a text and I fail to understand how Vout can equal 15 volts if the top mosfet has a resistance of 5k ohms.

 

[vk6kro]

That looks pretty mysterious.

If you are going to refer to a diagram, you need to include the diagram or redraw it and include that.

Generally, though, you probably know that if there is no current flowing in a resistor, there won't be a voltage across it. This seemed to answer what you were asking, but it is hard to be sure without a diagram.