Quadrilaterals
Name
Properties of Parallelograms
Date
I can …
Essential Question(s):
Key Concepts
Quadrilateral
Important Characteristics (2)
Types of Quadrilaterals
 Properties of Parallelograms
Notes
Special Parallelograms
Rhombus –
Rectangle –
Square –

How do I prove that
opposite sides are parallel?

How do I prove that
opposite sides are
congruent?

How do I determine if the
angle is a right angle?
Determining Types of
Quadrilaterals Examples
Note: When determining what
type of quadrilateral something is,
there are several key questions
that you need to consider…
Example 1.
The vertices of a quadrilateral are
A(2, 2), B(4, 6), C(8, 2), & D(10, 6).
What type of quadrilateral is it?
Prove it!
Example 2
The vertices of a quadrilateral are
𝐸(4, 2), 𝐹(5, 5), 𝐺(1, 3), & 𝐻(2, 6)
What type of quadrilateral is it?
Prove it!
Example 3
The vertices of a quadrilateral are
𝐽(1, 0), 𝐾(−3, 4), 𝐿(−2, −3),
𝑎𝑛𝑑 𝑀(−6, 1). What is this
quadrilateral? Prove it!
Example 4
Given quadrilateral ABCD with A
(−5, 0), B (−1, 4), C (−5, −6),
and D (7, 0)…
a) Find the midpoint of each
side labeling them E, F, G,
and H, respectively.
b) Connect the midpoints to
form a new quadrilateral,
EFGH.
c) Classify this quadrilateral
and explain why.
Answer to the Essential Question
Opposite sides are parallel
Opposite sides are congruent
Opposite angles are congruent
Angle sum is 360°
Both diagonals are congruent
Diagonals bisect each other
All four angles are right angles
Diagonals are perpendicular
Diagonals bisect each angle
All sides are congruent
Angles do NOT have to be right angles
Squares
Rectangles
Properties Chart
Parallelograms
Quadrilateral
Quadrilaterals
What I Think I know before the Lesson:
Opposite sides are parallel
Opposite sides are congruent
Opposite angles are congruent
Angle sum is 360°
Both diagonals are congruent
Diagonals bisect each other
All four angles are right angles
Diagonals are perpendicular
Diagonals bisect each angle
All sides are congruent
Angles do NOT have to be right angles
Squares
Rectangles
Properties Chart
Parallelograms
Quadrilateral
Quadrilaterals
What I Know after the Lesson: