Download Geometry 6-6 Trapezoids

Geometry 6-6 Trapezoids
• Only one pair of parallel sides (called bases)
• Non-parallel sides are called legs
• Base angles share a common base
Isosceles Trapezoid
•
•
•
•
Legs are congruent
Each pair of base angles are congruent
Top and bottom angles are supplementary
Diagonals are congruent
A
D
B
AC ≅BD
C
Examples
Find mA.
AD = 12x – 11, and
BC = 9x – 2. Find the
value of x so that
ABCD is isosceles.
Midsegment of a Trapezoid
• A midsegment of a trapezoid connects the
midpoints of the two legs (also called a
median).
Base
Midpoint
Midsegment
Base
Midpoint
Length of a Midsegment
• The midsegment of a trapezoid is the average
of the two bases.
base1  base2
midsegment 
2
Base 1
Midsegment
Base 2
Example
Find the length of EF.
10
F
E
24
Example
Find the length of AB.
A
B
19.5
32