**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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