## Individual Research Projects Section 7.5

### Project 7.5

Historical Quest
The Historical Note in Section 7.5 asks the question, Why did the Egyptians build the pyramids using a slant height angle of about 44° or 52°? Write a paper answering this question.

References:
Arthur F. SmithSee the whole entry

Videos:
This is a video discussing polygons (time: 6:35)

Low key introduction to angles (time: 9:55)

Here is a video on angles and parallel lines (time: 6:03)
See the whole entry

## Homework Hints 7-4

### Note: Homework Hints are given only for the Level 1 and Level 2 problems.

However, as you go through the book be sure you look at all the examples in the text. If you need hints for the Level 3 … See the whole entry

## Homework Hints 7-3

### Note: Homework Hints are given only for the Level 1 and Level 2 problems.

However, as you go through the book be sure you look at all the examples in the text. If you need hints for the Level 3 … See the whole entry

## Homework Hints 7-2

### Note: Homework Hints are given only for the Level 1 and Level 2 problems.

However, as you go through the book be sure you look at all the examples in the text. If you need hints for the Level 3 … See the whole entry

## 7.3 Outline

1. Terminology
1. six parts of a triangle
2. classifying triangles
1. by sides
1. scalene
2. isosceles
3. equilateral
2. by angles
1. acute
2. right
3. obtuse
3. congruent triangles
1. construction
2. corresponding parts
2. Angles of a triangle
1. angles in a triangle
2. exterior angle
3. exterior angle property
3. Isosceles triangle
See the whole entry

## 7.2 Outline

1. Angles
1. vertex (pl. vertices)
2. angle
3. notation for angles
4. equal angles
5. degree
6. classifications
1. acute
2. right
3. obtuse
4. straight
7. congruent angles
8. complementary angles
9. supplementary angles