1. Today we will define right angles, obtuse angles, and acute angles.

2. Think Pair Share What do you call the point where two lines meet? Corner

3. Degrees: Measuring Angles We measure the size of an angle (corner) using degrees. Example: Here are some examples of angles and their degree measurements.

4. Acute Angles An acute angle is an angle measuring between 0 and 90 degrees. Example:

5. Obtuse Angles An obtuse angle is an angle measuring between 90 and 180 degrees. Example:

6. Right Angles A right angle is an angle measuring EXACTLY 90 degrees. Examples:

7. On your whiteboards…. Is this angle acute, right, or obtuse?

8. On your whiteboards…. Is this angle acute, right, or obtuse?

9. On your whiteboards…. Is this angle acute, right, or obtuse?

10. On your whiteboards…. Is this angle acute, right, or obtuse?

11. On your whiteboards…. Is this angle acute, right, or obtuse?

12. On your whiteboards…. Is this angle acute, right, or obtuse?

13. On your whiteboards…. Is this angle acute, right, or obtuse?

14. On your whiteboards…. Is this angle acute, right, or obtuse?

15. What did we learn today? What is a right angle? What is an obtuse angle? What is an acute angle?