Washington State Department of Licensing Knowledge Test

On one-way roads, yellow lines are used as

1. Left edge lines

2. Center lines

3. Right edge lines

4. Passing lines

The correct answer is: Left edge lines

On one-way roads, yellow lines are used as left edge lines. This is important because yellow lines indicate that traffic flows in only one direction, assisting drivers in maintaining proper positioning on the road. When traveling on a one-way street, the yellow line serves as a guide, helping drivers to keep their vehicles on the appropriate side of the road and avoid head-on collisions. In contrast, center lines are typically used on two-way roads to separate traffic moving in opposite directions, while edge lines are marked along the sides of the road, helping to define the boundaries of the driving surface. Passing lines refer to markings that indicate whether passing is permitted, and these lines vary in color and pattern depending on the specific rules of the road, usually on two-way streets. Understanding these markings is crucial for safe driving practices.