martes, 25 de octubre de 2016

TRIANGLES AND QUADRILATERALS

TRIANGLES 

A triangle has three sides and three angles 
The three angles always add to 180°

TYPES OF TRIANGLES


QUADRILATERALS

Quadrilateral just means "four sides" (quad means four, lateral means side). Any four-sided shape is a QuadrilateralBut the sides have to be straight, and it has to be 2-dimensional 
TYPES OF QUADRILATERALS


General Properties 
        • Four sides (edges)
        • Four vertices or vertexes (corners)
        • The interior angles add up to 360 degrees:
Quadrilateral Angles
Try drawing a quadrilateral, and measure the angles. They should add to 360°

Individual Properties 
Check this web to learn more about them: 

viernes, 21 de octubre de 2016

NOTABLE POINTS AND LINES OF THE TRIANGLE

NOTABLE POINTS OF THE TRIANGLE:


CIRCUMCENTER, INCERTER, ORTHOCENTERResultado de imagen de triangle circumcenter incenter


The INCENTER and CIRCUMCENTER of an EQUILATERAL TRIANGLE are in the exact same point.
Resultado de imagen de triangle circumcenter incenter 


Paper folding - the perpendicular bisectors of a triangle

 

  http://www.regentsprep.org/regents/math/geometry/gc3/perpacute.gif


 

Paper folding - the angle bisectors of a triangle

 

http://www.regentsprep.org/regents/math/geometry/gc3/bisectoracute.gif 

 

BISECTORS AND... KITES?

It is time to get started with the compass! We will draw two VERY IMPORTANT constructions, used in technical drawing to construct almost everything, EVEN A KITE!

It is CRUCIAL that you learn how to do them by observing and practising. SO LETS DO IT!:

PERPENDICULAR BISECTOR LINE

Definition:

The perpendicular bisector is a PERPENDICULAR line that DIVIDES a line segment into TWO EQUAL parts. It also makes a right angle with the line segment. Each point on the perpendicular bisector is at the same distance from each of the endpoints of the original line segment.

It is basically a line which cuts a line segment into two equal parts at 90°.


 http://ceemrr.com/Geometry1/ParPerp/paste_image14.gif 
 




ANGLE BISECTOR LINE

Definition: 

It is a line that DIVIDES the angle in TWO EQUAL parts.

http://www.mathopenref.com/images/constructions/constbisectangle/proof.png




PRACTISE: 

USING THE ANGLE BISECTOR LINE TO CONSTRUCT A KITE


jueves, 6 de octubre de 2016