October 2007

1.4 Solve problems involving recognize, estimate and measure angles using the measurement unit Degree

Preliminary

geometry comes from the Greek " Geos "- land and" metron "- far, and arises in the early civilizations of the need to set limits for agricultural and urban land. Some of the early work we have of this branch of mathematics are: Papyrus

Ahmose ( Egypt): His original title is "Getting to know all secret things. " Contains arithmetic and geometry problems with solutions, but not with your procedure.

Babylonian Tables: divide the 360-degree turnaround from subdividing each of its 12 months governed by a different constellation (zodiac) in 30.

Works Thales of Miletus : First astronomer who accurately predicted an eclipse, and calculated by means of angles and shadows the total height of the Pyramid of Cheops .

School of Pythagoras : Inventor of the word mathematics. Founded the first school dedicated to mathematics, divided into 4 sections:
-
Absolute numbers or arithmetic or music-applied numbers
-magnitudes at rest or
-Magnitudes geometry or astronomy moving
His two most important theorems are :
-The sum of the angles interior of a triangle (180 °)
-theorem Pythagoras ( From the Middle Ages, was considered the " pons

asinorum " asses bridge, ie, knowledge

separating the educated from the uneducated)

"The Elements" of Euclid : The first work dedicated to a geometry, the chapters are called biblos . It contains all the basics of plane geometry (often also called Euclidean), to be followed by more than 2000 years.

First page of The Elements, the first printed edition in Latin in 1492, translated by Campanus

angles are the union of two lines that have one endpoint in common, the lines are called sides of angle and the common point is the vertex. The angles are measured by the amount of rotation, with the help of the Babylonian system. The fundamental unit is called the degree (º).

Angles are classified depending on the extent of their degrees:
-Acute Angle: 0 º and 90 º
-Angle = 90 º
-obtuse angle: more than 90 degrees and less than 180 º
-Straight Angle: = 180

The relations between angles can tell by their position or their action coupled

-Angles collinear : Those who share one side and the vertex angles
-vertical angles, only share the vertex, but one of its sides

are an extension of another angle.
-Complementary Angles: Those add up to 90 º
-Supplementary Angles: Those add up to 180 º

Drawing Exercise The following angles and classify them as:
1) 15 º
2) 20 º
3) 35 º
4) 45 º
5) 75 º
6) 90 º
7) 110 º
8) 135 °
9) 150 º
10) 175 º
11) Two angles vertical angles
12) Two complementary angles of 50 º and 40 º
13) Two complementary angles of 30 º and 60 º
14) Two supplementary angles of 100 º and 80 º
15) Two supplementary angles of 125 º and 55 º