Transcript 6.6 Trapezoids and Kites - Cardinal O'Hara High School
6.6 Trapezoids and Kites • A
trapezoid
is a quadrilateral with exactly one pair of parallel sides. • The parallel sides of a trapezoid are called
bases
.
• The nonparallel sides are called
legs
.
• Two angles that share a base of a trapezoid are called
base angles
.
• An
isosceles trapezoid
is a trapezoid with legs that are congruent.
Theorem 6.19
• If a quadrilateral is an isosceles trapezoid, then each pair of base angles is congruent.
Finding Angle Measures in Trapezoids • CDEF is an isosceles trapezoid and the measure of angle C = 65. What are the measures of angle D, angle E, and angle F?
65 180 115 180
m F m E
65 115
Theorem 6.20
• If a quadrilateral is an isosceles trapezoid, then its diagonals are congruent.
Midsegment of a Trapezoid
• The
midsegment of a trapezoid
that joins the midpoints of its legs.
is the segment – Is parallel to the bases.
– The length of the midsegment is half the sum of the lengths of the bases.
Kites
• A
kite
is a quadrilateral with two pairs of consecutive sides congruent and no opposite sides congruent.
Theorem 6.22
• If a quadrilateral is a kite, then its diagonals are perpendicular.
Finding Angle Measures in Kites
• Quadrilateral DEFG is a kite. What are the measures of angle 1, angle 2, and angle 3?
m
1 90 90 142
m m
180
m
2
m
3 38 52
Concept Summary
More Practice!!!!!
• Homework – Textbook p. 394 – 395 #7 – 36 ALL.