Cheatography

# Grade 9 Parallelograms Math (3rd Semester) Cheat Sheet by HeavenlySupreme

Lessons i remember from Math in the 3rd Semester as a Student of FTHS.

 Is a Four sided Polygon, having 4 Edges(­sides) Derived from latin words "­Qua­dri­" a Variation of Four and "­Lot­us" meaning Side. another name for it is "­tet­rag­on" Derived from the Greek word "­Tet­ra" meaning four and "­Gon­" meaning Corner or Angles

### Properties of a Parall­elogram

 Consec­utive Angles are Supple­mentary Parallel Sides are Congruent Opposite Angles are Congruent Diagonals Bisect each other Diagonals Bisect the Parall­elogram into two Congruent Triangles Diagonals are Congruent

### PROVING THEOREMS and POSTULATES

 VAT Vertical Angles Theorem Vertical angles are Congruent AAP Angle Addition Postulate if three Sides of one Triangles are Congruent to the Corres­ponding parts of another. then triangles are Congruent CPCTC Corres­ponding Parts of Congruent Triangles are Congruent LC Congruence Theorem if the Leg of another Right Triangle is Congruent, then the two Right Triangles are Congruent

### TRAPEZOID

 Is a Quadri­lateral in which are and only one pair of opposite sides are parallel The Parallel sides of a trapezoid are called BASES The Non-Pa­rallel sides are Called LEGS The pair of angles formed by a base and legs are called BASE ANGLES if the LEGS of the Trapezoid are Congruent, then the Trapezoid is called an ISOSCELES TRAPEZOID

 PARALL­ELOGRAM a quadri­lateral with two pairs of parallel sides RHOMBUS a quadri­lateral with two pairs of congruent sides RECTANGLE a quadri­lateral with four right angles SQUARE a quadri­lateral with four congruent angles and sides TRAPEZOID a quadri­lateral with one pair of parallel sides KITE a quadri­lateral with two distinct pairs of consec­utive sides that are congruent

### SPECIAL PROPERTIES

 Properties Parall­elogram Rectangle Opposite Sides are Parallel True True Opposite Angles are Congruent True True Consec­utive Angles are Supple­mentary True True Diagonals Bisect each other True True Either Diagonals form Two Congruent Triangles True True Pairs of Opposite Sides are Congruent and Parallel True True Opposite Sides are Congruent True True Diagonals are perpen­dicular False False Diagonals Bisect a pair of Opposite Angles False False Diagonals are Congruent False True Diagonals are Both Perpen­dicular and Congruent False False

### ISOSCELES TRAPEZOID

 an Isosceles Trapezoid features some special properties Legs are Congruent Base Angles are Congruent Diagonals are Congruent

### Median of Trapezoid

 is a Segment which Joints the Mid Points of the Non-Pa­rallel Sides. It is Parallel to the Bases and has a Length equal to 1/2 the sum of the length of the bases (Upper Base + Lower Base)/2