"Preliminary Understanding of Polygons and Circles" Basic Plane Graphics PPT Teaching Courseware

Description

"Preliminary Understanding of Polygons and Circles" Basic Plane Graphics PPT Teaching Courseware

Part One: Learning Objectives

1. Understand related concepts such as polygons, regular polygons, circles, sectors, etc. (Key points)

2. Be able to find the degree of the central angle of the sector based on the relationship between the sector and the circle. (Difficulty)

Preliminary understanding of polygons and circles PPT, part 2 content: teaching new lessons

polygon

collaborative inquiry

Triangles, quadrilaterals, pentagons, hexagons, etc. are all polygons.

Thinking: What kind of lines are these graphics made of and how?

Concepts related to polygons

A closed plane figure composed of several line segments that are not on the same straight line and connected end to end is called a polygon.

The line segments that make up a polygon are called the sides of the polygon.

The common endpoints of each two adjacent sides are called vertices of the polygon.

Tip: The polygons we usually refer to refer to convex polygons, that is, a polygon is always on the same side of the straight line where any side lies.

Exploration 1: The relationship between polygon sides, vertices and interior angles

Summary: An n-sided polygon has n vertices, n sides, and n interior angles.

Exploration 2: The relationship between polygon sides and diagonals

Question 1: How many diagonals are there through each vertex of the n-sided polygon? How many triangles can it be divided into?

Question 2: How many diagonals does an n-sided polygon have?

Task Assignment:

1. Assign a figure to each person, first draw all diagonals through a vertex; then fill in the corresponding data in the table;

2. Communicate in groups and summarize and complete all forms.

practice

1. A polygon can draw up to 2016 diagonals from a vertex. The number of sides of this polygon is ()

A. 2016 B. 2017

C． 2018 D. 2019

2. The line segments connecting one vertex of the nonagon and the other vertices divide the nonagon into _____ triangles.

Preliminary understanding of polygons and circles PPT, the third part: practice in class

1. Which of the following statements is correct ()

A. A closed figure formed by connecting several line segments that are not on the same straight line is called a polygon

B. The figure enclosed by an arc and two radii passing through the arc is called a sector.

C． Triangle is the simplest polygon

D． A sector is a part of a circle

2. Master Liu saw off one corner of a quadrilateral wooden board, then the shape of the remaining wooden board cannot be ()

A. Triangle b. quadrilateral

C． Pentagon D. hexagon

3. Divide a circle into four sectors, and the ratio of their central angles is 1:2:3:4. Then the central angles of these four sectors are ________, ________, ________, ________.

4. As shown in the figure, a circle is divided into four sectors. If the radius of the circle is 4 cm, can you find their areas?

Preliminary understanding of polygons and circles PPT, Part 4 content: Class summary

Preliminary understanding of polygons and circles

polygon

diagonal of polygon

diagonal of n-gon

split triangle

regular polygon

round

central angle

sector area

Keywords: Free download of Beijing Normal University version of seventh grade mathematics volume PPT courseware, preliminary understanding of polygons and circles PPT download, basic plane graphics PPT download, .PPT format;

For more information about the "Preliminary Understanding of Basic Plane Figures Polygons and Circles" PPT courseware, please click the "Basic Plane Figures PPT Preliminary Understanding of Polygons and Circles" PPT tag.

"Preliminary Understanding of Polygons and Circles" Basic Plane Graphics PPT Download:

"Preliminary Understanding of Polygons and Circles" Basic Plane Graphics PPT Download Part One Content: Learning Objectives 1. Understand the concept of polygons and know that triangles, quadrilaterals, pentagons, hexagons, etc. are all polygons. 2. Master the vertices and Side, interior angle, opposite angle...

"Preliminary Understanding of Polygons and Circles" Basic Plane Graphics PPT:

"Preliminary Understanding of Polygons and Circles" Basic Plane Figures PPT Part 1 Content: Knowledge Points Basic Knowledge Points 1 Polygons and their Concepts 1. Which of the following statements is incorrect (C) A. Triangle, quadrilateral, pentagon, hexagon They are all polygons B. Regular polygons..

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Update Time: 2024-09-01

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

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