1. POLYGONS CONVEX POLYGON CONCAVE POLYGON
At least one of its angles is bigger than 180º
All of its angles are smaller than 180º

2. POLYGONS 3 sides - 3 vertices 5 sides- 5 vertices 6 sides- 6 vertices
Triangle
Cuadrilateral
Pentagon
Hexagon …
3 sides - 3 vertices
5 sides- 5 vertices
4 sides - 4 vertices
6 sides- 6 vertices

3. TRIANGLES 2 equal sides 3 equal sides 3 different sides 2 equal angles
Clasification by relative lengths of its sides
equilateral
isosceles
escalene
2 equal sides
2 equal angles
3 equal sides
3 equal angles
3 different sides
3 different angles

4. TRIANGLES 3 angles smaller than 90º
Clasification by internal angles
acutangle
right
obtusangle
One of its angles is bigger than 90º
3 angles smaller than 90º
One of its angles is 90º

5. TRIANGLES INCENTER Bisector angles
ELEMENTS OF A TRIANGLE
Bisector angles
It is the centre of the inscribed circumference
INCENTER

6. TRIANGLES CIRCUMCENTRE Perpendicular bisector to each side
ELEMENTS OF A TRIANGLE
Perpendicular bisector to each side
It is the centre of the circumference that passes through all the vertices
CIRCUMCENTRE

7. TRIANGLES
ELEMENTS OF A TRIANGLE
Medians (Straitgh lines that links a vertice to the middle point of the opposite side
It is the gravity centre
INCENTRE

8. TRIANGLES ORTHOCENTRE
ELEMENTS OF A TRIANGLE
Altitudes (Perpendular lines from a vertex to the opposite side)
ORTHOCENTRE

9. CUADRILATERALS SQUARE Parallel and equal length of the sides
All the angles make 90º degrees

10. CUADRILATERALS RECTANGLE Parallel sides and equal two by two
90º degrees angles

11. CUADRILATERALS ROMBHUS Parallel sides two by two and equal lenght
Equal angles two by two
Perpendicular diagonals.

12. CUADRILATERALS RHOMBOID Parallel and equal sides two by two
Equal angles two by two

13. CUADRILATERALS TRAPEZIUM It has two parallel sides called bases
SMALLER BASE
BIGGER BASE

14. CUADRILATERALS TIPES OF TRAPEZIUM: Right (two angles of 90º degrees)
Isosceles (non parallel sides of equal lenght)
Right (two angles of 90º degrees)

15. CUADRILATERALS
TRAPEZOID
4 different sides
4 different angles