what does bearing/s of line/s mean in trigonometry?

The "bearing" means the direction of the line, relative to some fixed direction. Typically bearings are given in one of two ways:

1. As a "true bearing," measured in degrees clockwise from north. For example, a true bearing of 90 degrees means heading due east, and a true bearing of 350 degrees means 10 degrees to the left of north.

2. As a "relative bearing" measured in degrees from to the nearest north or south line. For example, "10 degrees west of north" is equivalent to a true bearing of 350 degrees, and 30 degrees east of south" is equivalent to a true bearing of 150 degrees.

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