Geometry

Clare Harris, Jun 26, 2014

Table of Contents

  1. Intro
    1. What's My Number Line Rule #1?
    2. What's My Number Line Rule #2?
    3. What's My Number Line Rule #3?
    4. What's My Number Line Rule #4?
    5. What's My Number Line Rule #5?
    6. What's My Number Line Rule #6?
    7. What's My Number Line Rule #7?
    8. What's My Number Line Rule #8?
  2. Intro Part II
    1. What's My Rule #1?
    2. What's My Rule #2?
    3. What's My Rule #3?
    4. What's My Rule #4?
    5. What's My Rule #5?
    6. What's My Rule #7?
    7. What's My Rule #8?
    8. What's My Rule #9?
    9. What's My Rule #10?
  3. Transformations
    1. Reflections
    2. Rotation of a figure
  4. Circles
    1. Exploring lines Tangent to a circle
    2. Two Tangents to a Circle
    3. Properties of Inscribed Angles in a Circle
  5. Quadrilaterals
    1. Properties of Parallelograms
    2. Poorly Drawn Quadrilaterals
  6. Angles and Lines
    1. Exterior Angles of Polygons
    2. Polygon interior angle sum patterns.
  7. Triangles
    1. Triangle Inequality Theorem

1.

Intro

  • 1. What's My Number Line Rule #1?
  • 2. What's My Number Line Rule #2?
  • 3. What's My Number Line Rule #3?
  • 4. What's My Number Line Rule #4?
  • 5. What's My Number Line Rule #5?
  • 6. What's My Number Line Rule #6?
  • 7. What's My Number Line Rule #7?
  • 8. What's My Number Line Rule #8?

1.1.

What's My Number Line Rule #1?

Drag point A along the number line and point B moves in response. What is the rule that point B follows?
What's my rule?
– Steve Phelps

1.2.

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1.3.

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1.4.

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1.5.

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1.6.

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1.7.

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1.8.

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2.

Intro Part II

  • 1. What's My Rule #1?
  • 2. What's My Rule #2?
  • 3. What's My Rule #3?
  • 4. What's My Rule #4?
  • 5. What's My Rule #5?
  • 6. What's My Rule #7?
  • 7. What's My Rule #8?
  • 8. What's My Rule #9?
  • 9. What's My Rule #10?

2.1.

What's My Rule #1?

What's my rule?
– Steve Phelps

2.2.

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2.3.

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2.4.

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2.5.

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2.6.

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2.7.

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2.8.

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2.9.

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3.

Transformations

  • 1. Reflections
  • 2. Rotation of a figure

3.1.

Reflections

Click on the checkboxes to see how the ordered pairs change when the figure is reflected over certain lines.
– Clare Harris

3.2.

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4.

Circles

  • 1. Exploring lines Tangent to a circle
  • 2. Two Tangents to a Circle
  • 3. Properties of Inscribed Angles in a Circle

4.1.

Exploring lines Tangent to a circle

Drag the center of circle A and point C around to change the circle. [br]Drag the angle measure to change the angle at which line EC intersects [br]the radius AC. Answer the guiding questions as you explore lines tangent[br]to a circle.
1. What is the difference between a tangent line and a secant line?[br]2. What are the characteristics of the sketch when the line is a secant? [br] a. list the number of intersection points, the relationship to the radius, the angle measure etc. [br]3. What are the characteristics of the sketch when the line is a tangent?[br] a. list the number of intersection points, the relationship to the radis, the angle measure etc.[br]4. Write a conjecture about the angle between the tangent line and the radius of the circle?
– Anthony DiLaura

4.2.

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4.3.

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5.

Quadrilaterals

  • 1. Properties of Parallelograms
  • 2. Poorly Drawn Quadrilaterals

5.1.

Properties of Parallelograms

Below is parallelogram ABCD. Drag the vertices and observe what happens. What conjectures can you make?
– Clare Harris

5.2.

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6.

Angles and Lines

  • 1. Exterior Angles of Polygons
  • 2. Polygon interior angle sum patterns.

6.1.

Exterior Angles of Polygons

[b]Click the "▶" button. Observe the angles turned by the car at the corners.[br]Drag the green points. Check the "Show Measurement" box to see the measurements of the angles.[br][/b]中文版：[url=https://ggbm.at/551]https://ggbm.at/551[/url]
[b]1. What is a + b + c + d + e, the total angles turned by the car?[br]2. a, b, c, d, e are called the exterior angles of the convex pentagon.[br]　　In general, what is the sum of all exterior angles of a convex polygon?[br]3. How would you modify the result if the pentagon is NOT convex?[br][/b][br]Anthony Or. GeoGebra Institute of Hong Kong.
– Anthony OR 柯志明

6.2.

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7.

Triangles

  • 1. Triangle Inequality Theorem

7.1.

Triangle Inequality Theorem

Adjust sliders a, b, and c until a triangle is formed.
What conclusion can you make about the side lengths necessary to form a triangle?
– Mathguru, rladage

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