3. NAMING a QUADRILATERAL and the PARTS of it
• Quadrilateral Name
• Sides
• Angles
• Diagonals
• Consecutive Angles
• Consecutive Sides
• Opposite Angles
• Opposite Sides
4. NAMING a QUADRILATERAL and the PARTS of it
• Quadrilateral Name
• Sides
• Angles
• Diagonals
• Consecutive Angles
• Consecutive Sides
• Opposite Angles
• Opposite Sides
11. QUADRILATERALS : FAMILY TREE
SQUARE – is a parallelogram
that has four congruent sides
and four right angles
12. QUADRILATERALS : FAMILY TREE
1. A rectangle is a parallelogram.
2. A square is a rhombus.
3. A square is a parallelogram.
4. A square is a quadrilateral.
5. A rhombus is a square.
6. A rectangle is a square.
7. A trapezoid is a quadrilateral.
8. A kite is a trapezoid.
9. A square is a rectangle.
10. A trapezoid is a parallelogram.
13. PARALLELOGRAM
A parallelogram is a quadrilateral that has two pairs of
opposite sides that are parallel.
PROPERTIES:
1. Opposite sides are congruent (≅).
2. Opposite angles are congruent.
3. Consecutive angles are
supplementary.
4. Diagonals bisect each other.
14. RHOMBUS
A rhombus is a parallelogram that has four congruent
sides.
PROPERTIES:
1. All properties inherited from the
parallelogram.
2. Diagonals are perpendicular (⊥).
3. Each diagonal bisects the angles of a
rhombus.
15. RECTANGLE
A rectangle is a parallelogram that has four right
angles.
PROPERTIES:
1. All properties inherited from the
parallelogram.
2. Diagonals are congruent.
16. SQUARE
A square is a parallelogram that has four congruent
sides and four right angles.
PROPERTIES:
1. All properties inherited from the
parallelogram.
2. All properties of rhombus.
3. All properties of a rectangle
17. Example:
A. Find the measures of the indicated parts
of parallelogram ABCD with diagonals
intersecting at point O using the properties
of a parallelogram.
1. AB =
2. BC =
3. OC =
4. DO =
5. 𝒎∠𝑫𝑨𝑩 =
6. 𝒎∠ABC =
7. Perimeter of parallelogram ABCD =
Hinweis der Redaktion
SIDES:
ABCD is a quadrilateral with four sides namely 𝑨𝑩̅̅̅̅, 𝑩𝑪̅̅̅̅, 𝑪𝑫̅̅̅̅ and 𝑫𝑨̅̅̅̅.
It has four vertices A, B, C and D. In naming a quadrilateral you may start at any vertex and move with the next vertex clockwise or counterclockwise.
ANGLES:
The angle between two adjacent sides is an angle of the quadrilateral. So, a quadrilateral has four angles that is, ∠DAB or ∠A, ∠ABC or ∠B, ∠BCD or ∠C and ∠CDA and ∠D.
Note: You may name an angle using a single letter/vertex if one angle shares that vertex.
A line segment joining a pair of opposite vertices is called a diagonal. So, there are two diagonals namely 𝑨𝑪̅̅̅̅ and 𝑩𝑫̅̅̅̅̅.
QUADRILATERAL NAME
MNOP, NOPM, OPMN, PMNO, MPON, NMPO, ONMP, PONM
SIDES
𝑴𝑵̅̅̅̅̅, 𝑵𝑶̅̅̅̅̅, 𝑴𝑷̅̅̅̅̅, 𝑷𝑶̅̅̅
ANGLES
∠𝑴, ∠𝑵, ∠𝑶, ∠𝑷
DIAGONALS
𝑴𝑶̅̅̅̅̅, 𝑵𝑷̅̅̅̅̅
Pairs of Consecutive Sides
𝑴𝑵̅̅̅̅̅ and 𝑵𝑶̅̅̅̅̅
𝑵𝑶̅̅̅̅̅ and 𝑷𝑶̅̅̅̅
𝑷𝑶̅̅̅̅ and 𝑴𝑷̅̅̅̅̅
𝑴𝑷̅̅̅̅̅ and 𝑴𝑵̅̅̅̅̅
Pairs of Opposite Sides
𝑴𝑵̅̅̅̅̅ and 𝑷𝑶̅̅̅̅
𝑵𝑶̅̅̅̅̅ and 𝑴𝑷̅̅̅̅
Pairs of Consecutive Angles
∠𝑴 and ∠𝑵
∠𝑵 and ∠𝑶
∠𝑶 and ∠𝑷
∠𝑷 and ∠𝑴
Pairs of Opposite Angles
∠𝑴 and ∠𝑶
∠𝑵 and ∠𝑷
1. 𝑨𝑩=?
Answer: 𝑨𝑩=𝟑𝟑, opposite sides are of a parallelogram are congruent, 𝑨𝑩̅̅̅̅ is the opposite side of 𝑫𝑪̅̅̅̅.
2. 𝑩𝑪=?
Answer: 𝑨𝑩=𝟏𝟎, opposite sides are of a parallelogram are congruent, 𝑩𝑪̅̅̅̅ is the opposite side of 𝑨𝑫̅̅̅̅.
3. 𝑶𝑪=?
Answer: 𝑶𝑪=𝟗, diagonals of a parallelogram bisect each other, 𝑨𝑶̅̅̅̅≅𝑶𝑪̅̅̅̅.
4. 𝑫𝑶=?
Answer: 𝑫𝑶=𝟏𝟏, diagonals of a parallelogram bisect each other, 𝑫𝑶 is half the measurement of 𝑩𝑫.
5. 𝒎∠𝑫𝑨𝑩=?
Answer: 𝒎∠𝑫𝑨𝑩=𝟏𝟎𝟖°, opposite angles are congruent, ∠𝑩𝑪𝑫≅∠𝑫𝑨𝑩.
6. 𝒎∠𝑨𝑩𝑪=?
Answer: 𝒎∠𝑨𝑩𝑪=𝟕𝟐°, consecutive angles are supplementary, the sum of 𝒎∠𝑩𝑪𝑫 and 𝒎∠𝑨𝑩𝑪 is 𝟏𝟖𝟎°.
7. Perimeter of parallelogram ABCD = ?
Answer: Perimeter of parallelogram ABCD =𝟔𝟒, perimeter is the sum of all sides, 32+10+32+10=64.