Warm Up
Crook Problems
Polygon:
 A many-sided plane figure, simple and
closed.
 Consists entirely of segments. (no curves)
 Consecutive sides intersect only at
endpoints.
 Each vertex must belong to exactly 2 sides.
Names of Polygons










3 sided:
4 sided:
5 sided:
6 sided:
7 sided:
8 sided:
9 sided:
10 sided:
12 sided:
15 sided:
triangle
quadrilateral
pentagon
hexagon
heptagon
octagon
nonagon
decagon
dodecagon
pentadecagon
Special Quadrilaterals:
 Parallelogram: a quadrilateral with both pairs of
opposite sides parallel.

 Rectangle: a parallelogram with 1 right angle.
 Rhombus: a parallelogram with all sides
congruent.
 Square: a rectangle and a rhombus.
Quadrilaterals: A four sided polygon
Special Quadrilaterals:
 Kite: a quadrilateral with 2 pairs of congruent
adjacent sides. (2 disjoint pairs of consecutive
sides)
 Trapezoid: a quadrilateral with 1 pair of parallel
sides. (called the bases, non-|| sides are the legs,
upper base angles and lower base angles)
 Isosceles Trapezoid: a trapezoid with congruent
legs.
Section 5.5
Objective: Students will be able
to identify properties of special
quadrilaterals.
Parallelograms
1.
2.
3.
4.
Opposite sides are ∥ and ≅.
Opposite angles are ≅.
Consecutive angles are supplementary
Diagonals bisect each other.
Rectangles
1.
2.
3.
It’s a parallelogram.
It has 4 right angles.
The diagonals are ≅.
Kites
1. Two pairs of ≅ adjacent sides.
2. The diagonals are ⊥.
3. One diagonal is the ⊥ bisector of the
other.
4. One of the diagonals bisects a pair of
opposite angles.
5. One pair of opposite angles are ≅.
Rhombuses
1. It’s a parallelogram and a kite.
2. All sides are congruent.
3. The diagonals are the perpendicular
bisectors of each other.
4. The diagonals bisect the angles.
5. The diagonals divide the rhombus into
four congruent right triangles.
Squares
1.
2.
It’s a rectangle and a rhombus.
The diagonals form four isosceles right ∆s. (45°–
45°–90° right ∆s)
Isosceles Trapezoids
1.
2.
3.
4.
The legs and base angles are ≅.
The bases are parallel.
The diagonals are ≅.
Consecutive base ∠s are
supplementary.
Venn Diagram




Using your quadrilateral properties,
place the names of the quadrilaterals
below in the Venn diagram.
Isosceles trapezoid  Rhombus
Rectangle
 Trapezoid
Square
 Parallelogram
Quadrilateral
Venn Diagram
Quadrilateral
Trapezoid
Isos. Trap.
Parallelogram
Rect. Sq.
Rhom.
Venn Diagram
Using the completed Venn diagram,
decide if each of the statements 1–10 is
true or false.
1.
2.
3.
4.
5.
False
False
True
True
False
6.
7.
8.
9.
10.
False
True
True
False (all are par.)
True
Show your work!
Homework
p.245 #5–7, 11-13, 19, 23
Exit Card
 Find the values of w, x, and y in the
parallelograms below.
36 °
(12w) °
90
144 °
2y
5x
80
50
Exit Slip
B
 Given: BCDF is a kite.
BC = 3x + 4y
CD = 20
BF = 12
FD = x + 2y
C
F
D
Find: The perimeter of BCDF.