Download GEOMETRY JOURNAL CHAPTER 6: THE MOVIE

SCRIPT:
By Christa Walters
Safety symbol: all Copyrights to
CW productions.
Don’t be afraid. It won’t kill you, only make you
stronger….
A closed figure that is formed by 3 or
more segments.
1. Side: one of the
segments that is part of
the polygon, which joins
the vertices.
2. Diagonal: segment that
connects any two
nonconsecutive
vertices.
3. Vertex: the common
endpoint between two
segments.
(Rosie standing by the
chair) says:
Jonathan responds by
telling her more
information: (eloquent,
teacher-like, and
demanding)
Convex
• A polygon in which on
or other vertices are
pointing in.
• A polygon in which the
vertices are pointing
concave out.
A POLYGON IN WHICH ALL
SIDES ARE CONGRUENT.
A POLYGON IN WHICH ALL
ANGLES ARE CONGRUENT.
The sum of the interior angle
measurement of a polygon with n
sides is (n-2)180
(Joe slowly
enters the
room and joins
the
conversation.)
EX
1. of an octagon: (8-2)180 = 1080/8= the m. of 1 angle=
135 degrees
2. Of a nonagon: (9-2)180= 1260/9= m. of 1 angle=
140 degrees
3. Of a pentagon: (10-2)180= 1440/10= m. of 1 angle= 144
degrees
(Rosie nods her
head and
continues to ask
questions)
A quadrilateral with two pairs of
parallel sides.Use the symbol ▭ to
name a parallelogram.
( already night time and Rosie still confused, has a dream about…………)
THEOREM 6-2-1
1. If a quadrilateral is a parallelogram,then its opposite sides are
congruent
(▭ ---- opp. Sides are congruent) (if opposite sides are congruent ---- it´s a▭)
B
C
A
D
AB congruent to CD
BC congruent to DA
THOREM 6-2-2
2. If a quadrilateral is a parallelogram,then uts opposite angles are congruent.
(▭---- opp. Angles are congruent)(if opposite angles are congruent,then it´s a ▭)
THOEREM 6-2-3
3. If a quadrilateral is a parallelogram, then its consecutive angles are
supplementary.
(▭----- cons..angles are supp)(if con.angles are supp.---then it is a ▭)
THEOREM 6-2-4
4. If a quadrilateral is a parallelogram, then its diagonals bisect each other,
(▭----diagnals bisect each other) (if diagonals bisect each other---- it´s a ▭)
Opposite sides are parallel
Opposite sides are
congruent
Consecutive
angles are
supplementary
Diagonals
bisect each
other
Opposite
angles ate
congruent
One set of
congruent and
parallel sides.
QUADRILATERAL
PARALLELOGRAM
RECTANGLE
RHOMBUS
SQUARE
A quadrilateral with exactly one pair of
parallel sides, each of the parallel sides is
called a base and the nonparallel sides
are called legs.
IF A TRAPEZOID IS ISOSCELES…. WHAT SHOULD ROSIE KNOW?
If a quadrilateral is an isosceles trapezoid, then each pair of base
angles are congruent.
If a trapezoid has one pair of congruent base angles,then the
trapezoid is isosceles.
A trapezoid is isosceles if and only if the diagonals are congruent.
The midsegment of a trapezoid is parallel
to each base and its length is one half the
sum of the lengths of the bases.
midsegment
mi
It’s a quadrilateral with exactly two pairs of congruent consecutive sides.
THEOREMS:
If a quadrilateral is a kite, then its diagonals are perpendicular.
If a quadrilateral is a kite,then exactly one pair of opposite angles are
congruent.