Friday, January 18, 2013

What are the special parallelograms?

* A Rhombus is a parallelogram with four congruent sides.
* the diagonals of a rhombus are perpendicular. the diagonals bisects the angles, and bisects each other.

* A Rectangle is a parallelogram with four congruent angles, or an Equiangular parallelogram.
* The diagonals of a rectangle are congruent and bisect each other.

*A Square is a equilateral rectangle or an equilangler rhomus.
* A Square's diagonals are congruent, perpendicular and they bisect each other.

MATH PROBLEM
The measures of the angles of a quadrilateral are x+15, 2x, x-45, and 2x-60. what types of quadrilateral could be this? 

1) parallelogram 

2) rectangle

3) Trapezoid

Sunday, December 9, 2012

What are the Properties of Kites?

Kite
Two pairs of consecutive congruent sides.
Properties of Kites
  • Non-vertex angles are congruent
  • Vertex angles are not congruent  

  • Diagonals are perpendicular
  • The vertex diagonal bisects the other diagonal
  • The vertex diagonal is an angle bisector of the vertex angle

How do we use Proberties of a Trapezoid?

Trapezoid
Exactly one pair of parallel sides.
Trapezoid Consecutive Angles Conjecture
the consecutive angles between the bases of a trapezoid are supplementary.

Isosceles Trapezoid Conjecture
The base angles of an isosceles trapezoid are congruent.



What are the Congruence Shortcuts?

Side-Angle-Side Triangle Postulate (SAS)
If two side of a triangle and the included angle are congruent to the two sides of another triangle and its included angle, then the two triangles are congruent.
 
  • The congruent angle must be between the congruent sides.
  • Triangles are congruent if any two sides and their included angle are equal in both triangles.


What are the Special Angles we can Create with Parallel lines?

Transversal
A line that intersects two or more other corresponding lines.

Corresponding Angles
Angles that are in the same position relative to the transversal and lines
  • If two parallel lines are cut by a transversal, then corresponding angles are congruent.
 
Alternate Interior Angles
If two parallel lines are cut by a transversal, then alternate interior angles are congruent.

 
 


 
Alternate Exterior Angles
If two parallel lines are cut by a transversal, then alternate exterior angles are congruent.