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Eight Angles Formed by Parallel Lines and a Transversal

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About This MicroSim

This static diagram shows the standard setup of two parallel lines (line l and line m) cut by a transversal (line t). The eight angles formed at the two intersection points are numbered 1 through 8, providing a reference for identifying the special angle pairs that arise from this configuration.

Key Concepts

Angle Pair Angles Relationship
Corresponding 1 & 5, 2 & 6, 3 & 7, 4 & 8 Congruent
Alternate Interior 3 & 5, 4 & 6 Congruent
Alternate Exterior 1 & 7, 2 & 8 Congruent
Same-Side Interior 3 & 6, 4 & 5 Supplementary (sum to 180)

Angle Numbering Convention

At each intersection, angles are numbered clockwise starting from the upper-left position:

  • Top intersection: Angles 1, 2, 3, 4
  • Bottom intersection: Angles 5, 6, 7, 8

Learning Objectives

  • Identify the eight angles formed when a transversal crosses two parallel lines
  • Name the four types of special angle pairs
  • State which pairs are congruent and which are supplementary

Bloom's Taxonomy Level

Remembering and Understanding -- Identifying and classifying angle pairs in the parallel-lines-and-transversal setup.

Iframe Embed Code

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