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An angle measures the amount of rotation between two rays that share a common endpoint called a vertex. Angles can be measured in degrees (°), and the measurement can range from 0° to 360°. For example, a right angle is 90°, a straight angle is 180°, and a full rotation is 360°.
Angles help us understand how much rotation occurs in various situations, from turning a corner to rotating a wheel. They can have different orientations, which brings us to the idea of coterminal angles.
Coterminal angles are angles that share the same initial and terminal sides but are different by whole multiples of 360°. This means you can add or subtract 360° to an angle to find other angles that look the same when drawn on a circle. For instance, 45° and 405° (45° + 360°) are coterminal.

Positive angles are measured counterclockwise from the initial side. When measuring angles, starting from the initial side (usually the positive x-axis), we measure in a counterclockwise direction to get a positive angle. For instance, if you rotate 60° counterclockwise, that's a positive 60° angle.
Finding coterminal angles often involves ensuring the angle is positive. For a given negative angle, we add 360° to make it positive. This ensures we find the smallest positive coterminal angle. For example, given -35°, adding 360° (one full rotation) gives us 325° (-35° + 360°), which is a positive angle.

A full rotation is equivalent to a 360° turn. This means if you rotate by 360°, you end up in the same position you started from. Understanding full rotations is important for finding coterminal angles. Since they differ by multiples of 360°, adding or subtracting full rotations will give angles that look the same on a circle but may have different numerical values.
Think of a clock as an analogy. Moving the minute hand 360° brings it back to the same number. Similarly, adding or subtracting 360° to an angle doesn't change its position on the unit circle. For example, 325° differs from -35° by one full rotation (360°) but both end up in the same position on the circle.