How do You Measure Angles?

In geometry, an angle is formed by two lines sharing a common endpoint, called vertex of the angle. The size of the angle will depend on the opening between the two lines that forms an angle and is measured in units that are referred to degrees. To measure an angle, a circular arc is drawn centered at the vertex of the angle. Then, the length of the arc is divided by the radius of the circle and possible multiplies by the scaling constant (which depends on the units of measurement that are chosen). The ratio of the length of the arc and the radius of the circle remains same, even for different size of the circle for the same, because when the radius of the circle changes, the length of the arc also changes in the same proportion. For more information see here: