Sec. 3.1: Identify Pairs of Lines and Angles Parallel lines are lines in the same plane that do not intersect. - презентация

1 Sec. 3.1: Identify Pairs of Lines and Angles Parallel lines are lines in the same plane that do not intersect.

2 Skew lines are lines not in the same plane that do not intersect. Line CD and line AG are skew.

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5 Angles formed by Transversals A transversal is a line that intersects two or more coplanar lines at different points. Angles that are between the two lines that are cut by the transversal are called interior angles. Angles 2, 4, 5 and 7 are interior angles. Angles that are not interior angles are called exterior angles. Angles 1, 3, 6 and 8 are exterior angles.

6 Special Angle Pairs formed by Transversals Transversals form special pairs of angles: Corresponding Angles Alternate Interior Angles Alternate Exterior Angles Consecutive Interior Angles

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8 Examples 3.Corresponding angles 4.Alternate Exterior angles 5.Alternate Interior angles