**Angles**

### Names and sizes of angles

Names and sizes of angles

In the figure below, angles *Y* and* α* are adjacent angles. Together they form a straight angle.

In the figure below, angles* α* and* β *are vertical angles. Vertical angles are equal.* α = β*

In the figure below, the lines* h* and* l *are parallel. Angles *α* and* Y* are congruent angles and equal.

*α = Y*

**Example 1**

Angle *α* is *25 *degrees. What is angle *β?*

Angles *α* and *β* together form a full angle.

**Example 2**

In the figure below, the lines *h* and* l* are parallel and angle* Y* is *35* degrees. What is angle* ω*?

Angles *Y* and* α* are congruent angles, so *Y = α* and angles *α *and* ω* form a straight angle, so

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