Quadrilaterals

Good morning everyone!

Before we will start our discussion for

this day, let’s have a prayer first. I

request everyone to please stand up.

QUADRILATERALS

A Quadrilateral is a polygon with four

sides.

Quadrilateral just means “four sides”. (quad means

four, lateral means side).

A Quadrilateral has four-sides, 2-

dimensional (a flat shape), closed (the lines join up),

and has straight sides.

Properties of Quadrilaterals: Four sides (edges)

Four vertices (corners)

The interior angles add up to 360 degrees

1. Parallelogram

2. Rectangle

3. Rhombus

4. Square

5. Trapezoid

6. Kite

Types of Quadrilaterals:

1. Parallelogram

A Parallelogram

is a quadrilateral with two

pairs of opposite sides

parallel to each other.

Opposite angles are also

equal.

2. RectangleA Rectangle is

a four-sided shape where

every angle is a right

angle (90°). The opposite

sides are also parallel and

equal in length.

3. RhombusA Rhombus is a four-sided shape where all sides

have equal length. The opposite sides are also

parallel and opposite angles are equal. The diagonals bisect

each other and meet in the middle at a right angle.

4. Square

A Square has

equal sides and all

angles are right angles

or measures 90°. The

opposite sides are also

parallel.

5. TrapezoidA Trapezoid is a quadrilateral with exactly

one pair of opposite sides parallel to each other called

the bases. The other non-parallel sides are called the

legs.

It is called an Isosceles Trapezoid if the

sides that aren't parallel are equal in length and

both angles coming from a parallel side are equal.

6. KiteA Kite has two pairs of

sides. Each pair is made up of

adjacent sides that are equal in length.

The angles are equal where the pairs

meet. Diagonals meet at a right angle,

and one diagonal bisects the other.

Family Tree

102A1.

A

B262.

Examples: Angles in Quadrilateral

Direction: Find the Angles marked with letters.

A

CB

68

88

62

2.

120

84A

B1.

Exercise 1: Angles in Quadrilateral

Direction: Find the Angles marked with letters.

Assignment:

Using the Venn diagram, present

the relationship of the types of

Quadrilaterals. Write it in a one whole

sheet of intermediate paper and pass it next

meeting.

Prepared by:

Francisco,

Reymond C.

1) 102 + 90 + 90 + A = 360

282 + A = 360

A =

360 - 282

A = 7

102A

Examples: Angles in Quadrilateral

Solutions:

back

2) 2A + 2B= 360

B = (90

+ 26)

B = 116

2A + 2(116) = 360

2A + 232 = 360

2A

= 360 - 232

2A= 128

A =

A = 64

Examples: Angles in Quadrilateral

Solutions:

A

B26

back

1) A = 84

A + B + 90 + 120 = 360

84 + B + 90 + 120 = 360

B + 2 = 360

B = 360 - 2

B = 6

Exercise 1: Angles in Quadrilateral

Solutions:

120

84A

B

back

A

CB

68

88

62

2) 88+ B + 68 + 62 = 360

B + 218 =

360

B = 360 - 2

B = 142

Exercise 1: Angles in Quadrilateral

Solutions:

A + 68 + 62 = 180

A + = 180

A = 180 -

130

A =

5

Exercise 1: Angles in Quadrilateral

Solutions:

C + 88 + 62 = 180

C+ = 180

C = 180 -

150

C =

3

A

CB

68

88

62 back