Areas/Heights

Marina Menna Barreto, Renert School, Feb 11, 2020

Table of Contents

  1. Circle
    1. Area of Circle
    2. Area of a Circle
    3. Area of Circles
    4. area of circle
    5. Area of a circle
  2. Quadrilaterals
    1. Area of a parallelogram
    2. Area of a trapezoid
    3. parallelogram heights
  3. Triangles
    1. Area of a triangle
    2. Triangle heights
    3. kangaroo 2004
  4. Exterior Angles
    1. Copy of Exterior Angles of Polygons

1.

Circle

  • 1. Area of Circle
  • 2. Area of a Circle
  • 3. Area of Circles
  • 4. area of circle
  • 5. Area of a circle

1.1.

Area of Circle

– Muru_Raj_10

1.2.

–

1.3.

–

1.4.

–

1.5.

–

2.

Quadrilaterals

  • 1. Area of a parallelogram
  • 2. Area of a trapezoid
  • 3. parallelogram heights

2.1.

Area of a parallelogram

Use this applet to understand the relationship between the formula for the area of a rectangle and the formula for the area of a parallelogram.
– Duane Habecker

2.2.

–

2.3.

–

3.

Triangles

  • 1. Area of a triangle
  • 2. Triangle heights
  • 3. kangaroo 2004

3.1.

Area of a triangle

Use this applet to see one reason why the formula for the area of a triangle is 1/2(bh).
– Duane Habecker

3.2.

–

3.3.

–

4.

Exterior Angles

  • 1. Copy of Exterior Angles of Polygons

4.1.

Copy of 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.
– Renert School, Anthony OR 柯志明

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