Central Angles and Arc Measures (Part 1)
Working with circles involves finding arc measures based on central angles. When a central angle forms at a circle's center, it creates an arc on the circle's circumference with the same measure in degrees.
To find arc measures, we often use the fact that a complete circle measures 360°. This means when you know some arc measures, you can find others by adding or subtracting from 360°. For example, if you know one arc measures 104°, its complementary arc would be 256° .
When dealing with equations involving central angles, set up an equation and solve for the variable. For instance, if a central angle is expressed as °, and you know it forms part of a straight angle (180°), you can write: 31° + ° = 180° and solve for x.
Try This: When working with central angles, always check your answer by substituting back into the original equation. This verification step helps catch calculation errors before moving to the next problem!


























