"Determination of Parallel Lines" Proof of Parallel Lines PPT download

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"Determination of Parallel Lines" Proof of Parallel Lines PPT download, 20 pages in total.

Part One: Learning Objectives

Use the angle relationship to determine whether two straight lines are parallel

Use the "third straight line" to determine whether two straight lines are parallel

Judgment of Parallel Lines PPT, Part 2: Gaining New Knowledge

Knowledge point: Use the angle relationship to determine whether two straight lines are parallel

1. Determination axiom of parallel lines: If two straight lines are intercepted by a third straight line, if the angles are equal, then the two straight lines are parallel.

Brief description: The parallel angles are equal and the two straight lines are parallel.

2. The determination axiom of parallel lines is an important basis for proving that straight lines are parallel.

3. Expression:

As shown in the figure: Because ∠1=∠2 (known),

So a∥b (the angles of the same angles are equal and the two straight lines are parallel).

Knowledge point: Use the "third straight line" to determine whether two straight lines are parallel

1. Determination Theorem 1

(1) Known: As shown in the figure, ∠1 and ∠2 are the internal offset angles of straight line a and b intercepted by straight line c, and ∠1=∠2.

Verification: a// b.

Proof: ∵∠1=∠2 (known),

∠1=∠3 (the two vertex angles are equal),

∴∠3=∠2 (equivalent substitution).

∴a//b (the parallel angles are equal and the two straight lines are parallel).

Judgment of Parallel Lines PPT, Part 3: Class Summary

The determination of parallel lines is based on the quantitative relationship between angles to the determination of the positional relationship between straight lines. To determine whether two straight lines are parallel, you can find whether concentric angles, internal angles, or internal angles on the same side are equal or complementary around the cross-section. When choosing one of these methods to indicate that two straight lines are parallel, you generally need to combine knowledge of opposite vertex angles, complementary angles, etc. to explain.

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For more information about the "Proof of Parallel Lines and Judgment of Parallel Lines" PPT courseware, please click on the Proof of Parallel Lines PPT Judgment of Parallel Lines PPT tab.

"Determination of Parallel Lines" Proof of Parallel Lines PPT teaching courseware:

"Determination of Parallel Lines" Proof of Parallel Lines PPT teaching courseware, 17 pages in total. Part 1: Basic knowledge points Knowledge point 1 Two straight lines with equal angles are parallel 1. In the following figure, from 1=2, AB∥CD must be obtained (A) 2. As shown in the figure, in the same plane..

"Determination of Parallel Lines" Proof of Parallel Lines PPT:

"Determination of Parallel Lines" Proof of Parallel Lines PPT, 20 pages in total. Part One: Learning Objectives 1. Understand and master the axioms and theorems of parallel lines. (Key points) 2. Understand the general steps of proof. (Difficulty) ... ... ... Judgment of parallel lines PPT,...

"Determination of Parallel Lines" PPT courseware download of intersecting lines and parallel lines:

"Determination of Parallel Lines" PPT Courseware Download of Intersecting Lines and Parallel Lines Part One Content: Learning Objectives 1. Master the three determination methods of parallel lines, and be able to use the determination methods to determine whether two straight lines are parallel; (Key Points) 2. Be able to judge based on How to determine parallel lines...

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Update Time: 2024-11-22

This template belongs to Mathematics courseware Beijing Normal University Edition Eighth Grade Mathematics Volume 1 industry PPT template

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