Lesson Materials

Lesson 7-1: Angle Measures

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The student will be able to give angle measures in degrees and radians and locate coterminal and reference angles.

  1. Drag the red point to change the angle on the graph.
  2. The alpha angle is in "Standard Position." Notice that one ray of the angle stays in the same place. Where is the other ray when the angle is 0 degrees? 90°? 180°? 270°? 360°?
  3. Now notice the relationship between the alpha angle and the theta angle. The theta angle is called the "Reference Angle."
unit circle

Clark U: Online notes on degree and radian measures. Clark U
Interactive Math: Online notes on degree and radian measures.Interactive Math

  1. Click the button for an Online Puzzle