Download Geometry Fall 2011 Lesson 17 (S.A.S. Postulate)

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Lesson Plan #55
Class: Geometry
Date: Friday January 15th, 2015
Topic: Kite
Aim: What are some properties of a kite?
Objectives:
1) Students will be able to use the properties of a Kite
HW #55:
Page 193 #’s 28-29
Do Now
1) Mark a point in the center of the open space at the
right. Mark this point as O. Using point O construct
a circle.
2) Construct a diameter through point O. Label the
diameter as AB .
3) Construct the perpendicular bisector of AB .
4) Label the intersection points of the circle and
The perpendicular bisector of AB as
CD
5) What figure is formed by connecting points
A, C, B, and D in that order?
_____________________________________
PROCEDURE:
Write the Aim and Do Now
Get students working!
Take attendance
Give Back HW
Collect HW
Go over the Do Now
Assignment #1: Discuss in your groups:
At the right we have a kite, which is defined as a quadrilateral
with two distinct pairs of adjacent sides that are congruent.
Draw in the diagonals of the kite.
What can you state about the diagonals of a kite? Why?
What are some other properties of a kite that can be
proven? Do not write out the proofs; just plan them!
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Summary of the properties of a kite:
The diagonals are perpendicular.
ONE diagonal bisects the other.
ONE diagonal bisects opposite angles.
ONE pair of opposite congruent angles.
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d1  d 2
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The area of the kite is
Fill-ins:
1) If all four sides of a kite have the same length (that is, if the kite is equilateral), it must be a _______________.
2) If a kite is
equiangular, meaning that all four of its angles are equal, then it must also be equilateral and thus
a _______________
Sample Test Questions:
1)
2)
Assignment #3:
Construct an equi-diagonal non-square, non-rhombus kite;
that is a kite whose diagonals are equal in length, making sure
the kite is not a square or rhombus.
Assignment #4:
Given that quadrilateral ABCD at the right is a kite:
1) Draw in diagonal AC. Label the intersection of the diagonals E.
2) Find rBD C  _____
 


TAB  A ______ RE ,180o EC _________ rAB TDA D  ________
o
3) If AB = 6 and m<ABC = 60 , find:
AC _____ BC ______ AE ______ CE _________ BE ______
4) Describe a precise sequence of rigid motions that would show ABD  CBD
5) Given the information from part 3 abo e, if DE = 6, find
A) area of kite ABCD _____
AD ________
CD __________ perimeter of kite ABCD _______
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If enough time:
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