Transcript Objectives • State the properties of trapezoids and kites

Objectives
• State the properties of trapezoids and
kites
• Solve problems involving kites and
trapezoids
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Trapezoid Definitions
• The parallel sides of a trapezoid are the
bases
• The non-parallel sides of a trapezoid are
the legs
• The angles that share a base are the base
angles.
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Theorem 6-15 Base Angles of Isosceles Trapezoid
• The base angles of an isosceles trapezoid
are congruent.
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Example: Base angles of isosceles trapezoid
Same side interior angles are suppl.
Substitution
Subtraction
The base angles of an isosceles
trapezoid are congruent.
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Theorem 6-16
• A trapezoid is isosceles if and only if its
diagonals are congruent
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Example: Diagonals of Isosceles Trapezoid
JN = 10.6, and NL = 14.8.
Find KM.
Isos. trap. s base 
KM = JL
JL = JN + NL
Def. of  segs.
KM = JN + NL
Substitute.
Segment Add Postulate
KM = 10.6 + 14.8 = 25.4 Substitute and simplify.
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Theorem 6-17 Diagonals of a Kite
• The diagonals of a kite are perpendicular
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Example: Diagonals of a Kite
Diagonals of a kite are perpendicular
∠2 is the complement of ∠DBC
BD ≅ BD
Reflexive Prop. of Congruence
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