"Properties of Parallel Lines" PPT Courseware 3

Description

"Properties of Parallel Lines" PPT Courseware 3

learning target

1. Through practical operations, explore the property: "When two parallel straight lines are intercepted by a third straight line, their co-position angles are equal." And through reasoning, understand the properties of "two parallel straight lines intercepted by a third straight line, the interior angles are equal" and "the interior angles on the same side are complementary".

2. Be able to use the properties of parallel lines to solve problems related to "three lines and eight angles".

3. Experience observation, reasoning, communication and other activities to develop spatial concepts, organized thinking and language expression skills.

Observe and think

Lines a and b are intercepted by line c, and a//b.

(1) Observe any pair of homotopic angles and use the superposition method or measurement method to explore the relationship in groups?

Properties of parallel lines 1

When two parallel straight lines are intercepted by a third straight line, their co-position angles are equal. This is simply called: two straight lines are parallel and their co-position angles are equal.

Lines a and b are intercepted by line c, and a//b.

(2) Observe any pair of internal offset angles, use the property 1 of parallel lines to explore the relationship?

When two parallel straight lines are intercepted by a third straight line, their interior offset angles are equal. This is simply called: two straight lines are parallel and their interior offset angles are equal.

Lines a and b are intercepted by line c, and a//b.

(3) Observe any pair of interior angles on the same side and use the property 1 of parallel lines to explore the relationship?

Properties of parallel lines 3

Two parallel straight lines are intercepted by a third straight line, and the interior angles on the same side are complementary. Abbreviation: Two straight lines are parallel, and the interior angles on the same side are complementary.

Class exercises

1. As shown in the figure, straight lines a and b are intercepted by straight line c, and a//b, if ∠1=65⁰, then ∠2=( ), the basis is ( ), ∠3=( ), the basis is ( )

2. Two parallel straight lines are intercepted by a third straight line, ∠1 and ∠2 are interior angles on the same side, and ∠1=50⁰, then ∠2=( )

A 50⁰ B 130⁰ C 50⁰ or 130⁰ D 40⁰

3. As shown in the figure, A is a point on the straight line DE, DE//BC, ∠B=38⁰, ∠C=57⁰, find:

(1) Degree of ∠DAB

(2) Degree of ∠EAC

(3) Degree of ∠BAC+∠B+∠C

untie:

(1) Because DE//BC

So ∠DAB=∠B=38⁰

(2)Because DE//BC

So ∠EAC=∠C=57⁰

(3) ∠BAC+∠B+∠C=∠BAC+∠DAB+∠EAC=180⁰

Class summary

Properties of parallel lines:

1. When two parallel straight lines are intercepted by a third straight line, the angles of the same angles are equal. This is simply called: two straight lines are parallel and the angles of the same angles are equal.

2. Two parallel straight lines are intercepted by a third straight line, and the internal offset angles are equal. Abbreviation: two straight lines are parallel, and the internal offset angles are equal.

3. Two parallel straight lines are intercepted by a third straight line, and the interior angles on the same side are complementary. Abbreviation: Two straight lines are parallel, and the interior angles on the same side are complementary.

Homework assignment

1. Must-do questions

Exercises 1 and 2 on page 36 of the textbook

Exercises 1-4 on page 37 of the textbook

2. Optional questions

Exercise 5 on page 37 of the textbook

Keywords: Teaching courseware on the properties of parallel lines, Qingdao edition seventh grade mathematics volume 2 PPT courseware download, seventh grade mathematics slide courseware download, Properties of parallel lines PPT courseware download, .PPT format;

For more information about the "Properties of Parallel Lines" PPT courseware, please click on the "Properties of Parallel Lines" ppt tab.

"Properties of Parallel Lines" PPT download:

"Properties of Parallel Lines" PPT Download Part 1 Content: Review Review What are the methods for determining parallel lines? How to identify parallel lines: (1) the angles of the same angles are equal, two straight lines are parallel (2) the internal angles are equal, the two straight lines are parallel (3) the internal angles on the same side are complementary, Two straight lines are parallel...

"Properties of Parallel Lines" PPT:

"Properties of Parallel Lines" PPT Part One Content: Knowledge Review 1. If B=1, according to _______________, we can get AD//BC 2. If 1=D, according to _______________, we can get AB//CD 3. If B+BCD=180, according to___..

"Properties of Parallel Lines" PPT courseware download:

"Properties of Parallel Lines" PPT courseware download Part 1 content: Do a hands-on experiment: Select any two parallel lines a, b on the prepared grid book (1) Draw a straight line c and parallel lines a, b arbitrarily intersect. (2) Choose any pair of co-positioned angles and measure them with a protractor...

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Update Time: 2024-11-13

This template belongs to Mathematics courseware Qingdao Edition Seventh Grade Mathematics Volume 2 industry PPT template

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