Types and Pairs of Angles

Types of Angles

• Acute Angle: An angle measuring less than 90 degrees.

• Right Angle: An angle measuring exactly 90 degrees.

• Obtuse Angle: An angle measuring more than 90 degrees but less than 180 degrees.

• Straight Angle: An angle measuring exactly 180 degrees.

• Reflex Angle: An angle measuring more than 180 degrees but less than 360 degrees.

Special Angle Pairs

1. Corresponding Angles:

   • Formed when a transversal crosses two parallel lines.
   • Located in the same position in relation to the parallel lines.
   • Are equal in measure.

2. Alternate Interior Angles:

   • Formed when a transversal crosses two parallel lines.
   • Located on opposite sides of the transversal and inside the parallel lines.
   • Are equal in measure.

3. Consecutive (Co-interior) Angles:

   • Formed when a transversal crosses two parallel lines.
   • Located on the same side of the transversal and inside the parallel lines.
   • Are supplementary (add up to 180 degrees).

4. Vertically Opposite Angles:

   • Formed when two lines intersect.
   • Located opposite each other at the intersection point.
   • Are equal in measure.

Visual Representation (if applicable)

• Consider drawing diagrams to illustrate each type of angle and their relationships, especially for corresponding, alternate interior, co-interior, and vertically opposite angles.

Types of Angles

• Acute Angle: Measures less than 90 degrees, representing sharp angles.
• Right Angle: Measures exactly 90 degrees, often marked with a small square.
• Obtuse Angle: Measures more than 90 degrees but less than 180 degrees, creating a wider opening.
• Straight Angle: Measures exactly 180 degrees, appearing as a straight line.
• Reflex Angle: Measures more than 180 degrees but less than 360 degrees, creating a backward or larger opening.

Special Angle Pairs

• Corresponding Angles:

  • Equal in measure and located in the same position relative to the two parallel lines when a transversal intersects them.

• Alternate Interior Angles:

  • Equal in measure and found on opposite sides of the transversal, positioned inside the two parallel lines.

• Consecutive (Co-interior) Angles:

  • Supplementary angles that add up to 180 degrees and are located on the same side of the transversal but inside the parallel lines.

• Vertically Opposite Angles:

  • Equal in measure and located across from each other at the intersection of two lines.