Originally Posted by
cyccommute
Technically this is incorrect. The laws state that an uncontrolled intersection should be treated like a 4-way stop or inoperable stoplight. In other words, you should yield to the car to your right. If they arrive at the same time, vehicle A has the right of way as it is the vehicle to the right.
Unfortunately this is not the way that that most people think and anyone in vehicle A would be foolish to try and assert their right of way.
In WA this is correct UNLESS one of the roads is classified as an arterial. (which is something you just have to know, there are no signs for that). Arterials have the right of way.
It's not clear to me if both the roads in this T are even roads at all (vs lanes in a parking lot).