Angle Relationships of Two Intersecting Lines [pptime time="0:01"](0:01) [/pptime]

When two lines intersect, they form special types of angle relationships: 🌟 What Are Vertically Opposite Angles? Definition: Vertically opposite angles are the angles formed across from each other when two lines intersect. Feature: Vertically opposite angles are always equal. 🌟 What Are Adjacent Angles? Definition: Adjacent angles share a common side and a common vertex. Key Fact: The sum of two adjacent angles can be any value. Special Case: If adjacent angles lie on a straight line , their sum is $180^\circ$. 🌟 What Are Supplementary Angles? Definition: Any two angles that sum to $180^\circ$ are supplementary. Key Difference: Supplementary angles are any two angles that sum to $180^\circ$, whether they are adjacent or not.

Angle Relationships in Parallel Lines and a Transversal [pptime time="0:45"](0:45) [/pptime]

A transversal is a straight line that crosses two or more other lines. When a transversal crosses two parallel lines , it forms special pairs of angles: 🌟 What Are Corresponding Angles? Corresponding angles are pairs of angles that lie on the same side of the transversal and in the same position at each intersection. Corresponding angles are equal if the lines are parallel. 🌟 What Are Alternate Interior Angles? Alternate interior angles are pairs of angles that lie between the two lines and on opposite sides of the transversal. Alternate interior angles are equal if the lines are parallel. 🌟 What Are Co-Interior Angles? Co-interior angles are pairs of angles that lie between the two lines and on the same side of the transversal. Co-interior angles add up to $180^\circ$ if the lines are parallel.

Angle Relationships in Intersecting and Parallel Lines

🎬 Video: Angle Relationships Explained

Angle Relationships of Two Intersecting Lines (0:01)

When two lines intersect, they form special types of angle relationships:

🌟 What Are Vertically Opposite Angles?

Definition: Vertically opposite angles are the angles formed across from each other when two lines intersect.
Feature: Vertically opposite angles are always equal.

🌟 What Are Adjacent Angles?

Definition: Adjacent angles share a common side and a common vertex.
Key Fact: The sum of two adjacent angles can be any value.
Special Case: If adjacent angles lie on a straight line, their sum is $180^\circ$.

🌟 What Are Supplementary Angles?

Definition: Any two angles that sum to $180^\circ$ are supplementary.
Key Difference: Supplementary angles are any two angles that sum to $180^\circ$, whether they are adjacent or not.

Angle Relationships in Parallel Lines and a Transversal (0:45)

A transversal is a straight line that crosses two or more other lines.

When a transversal crosses two parallel lines, it forms special pairs of angles:

🌟 What Are Corresponding Angles?

Corresponding angles are pairs of angles that lie on the same side of the transversal and in the same position at each intersection.
Corresponding angles are equal if the lines are parallel.

🌟 What Are Alternate Interior Angles?

Alternate interior angles are pairs of angles that lie between the two lines and on opposite sides of the transversal.
Alternate interior angles are equal if the lines are parallel.

🌟 What Are Co-Interior Angles?

Co-interior angles are pairs of angles that lie between the two lines and on the same side of the transversal.
Co-interior angles add up to $180^\circ$ if the lines are parallel.