Understanding Angles with a Protractor Diagram | Geometry Guide #118012 (License: Personal Use)

This diagram displays a semicircular protractor marked in 10-degree increments from 0° to 180°, with two rays originating from the center: one horizontal (0°) and one angled upward-left (~165°). The blue dotted ray clearly highlights an obtuse angle, making it ideal for teaching angle classification and measurement techniques in geometry education.

Used in educational web pages, math tutorials, or interactive geometry tools to help students visualize and practice angle measurement; matches user intent for learning basic trigonometry or preparing for standardized math tests.