ELECTIVE MATH 7 (2ND GRADING PERIOD)

ELECTIVE MATH 7 (2^ND GRADING PERIOD)

COURSE OUTLINE:

CHAPTER 7

Lesson 1 : The Three Elements of Geometry

Lesson 2 : Segment and Their Measures

Lesson 3 : Angles and their Measurement

Lesson 4 : Use a Protractor

Lesson 5 : Plane Figures

Lesson 6 : Use of the Compass

Lesson 7 : Three-Dimensional Figures

Review (Lesson 1 & 2)

GEOMETRY – the word geometry comes from the two ancient Greek word, geo, meaning EARTH, and metria meaning MEASURE. So literally, Geometry means to measure the earth.

UNDEFINED TERMS:

1.    POINT – is the simplest and yet most important building block in geometry. It is a location and occupies no space.

How to sketch:

                  Using “ — “or “ x”

How to label:

                Use capital letter

N Remember: Never name two points with same letter in the same sketch.

Example:

a.    — A           —B           The three dots represent points C,M,Q

         —C

b.    Z            Point Z or —Z

2. LINE – Are infinite series of points. Infinite means without end. A Line extends infinitely in two opposite directions but has no width and height.

 

3. PLANE – is infinite set of points extending in all direction along perfectly that surface. It is infinity long and infinity wide. A plane has a thickness or height of zero.

 

MEASUREMENT OF LINE SEGMENT

- The measure of line segment is the length of the line segment. Use the name of the line segment without the line above the name.

MIDPOINT

- Of a line segment divides the line segment into two congruent segments.

Lesson 3 : Angles and their Measurement

Angles

- is formed by two rays that have a common (or shared endpoints). The rays form the sides of the angle, and their endpoint forms its vertex.

 

It is customary to use small letters in the Greek alphabet to symbolize angle measurement. 

Name the angle by using the symbol < and the letter representing the vertex. For example from the figure below named as <ABC or <CBA. The middle letter B represents the vertex. This angle can be named also as <B. It may also be named by a greek letter, number or a lower case letter inside the angle, so it is <β.

  

OTHER TYPES OF ANGLES

11.    Adjacent angles – are two angles that share a vertex and a common side that separates them. Angles 1 and 2 are examples of adjacent angles.

12.    Vertical angles – When two lines intersect so as form angles, the angles on opposite side of the common vertex.

13.       Complementary angles – any two angles that add up to 90°.

 

14.       Supplementary angles – When two angles add up to a total of 180°.