2.7.5 Kites & Trapezoids
The student is able to (I can):
• Use properties of kites and trapezoids to solve problems
kite A quadrilateral with exactly two pairs of
congruent consecutive nonparallel sides.
Note: In order for a quadrilateral to be a
kite, nononono sides can be parallel and opposite
sides cannot be congruent.
If a quadrilateral is a kite, then its
diagonals are perpendicular.
If a quadrilateral is a kite, then exactly one
pair of opposite angles is congruent.
Example In kite NAVY, m∠YNA=54º and
m∠VYX=52º. Find each measure.
1. m∠NVY
90 — 52 = 38º
2. m∠XYN
3. m∠NAV
63 + 52 = 115º
N
A
V
Y
X
−
= = °
180 54 126
63
2 2
trapezoid A quadrilateral with exactly one pair of
parallel sides. The parallel sides are called
basesbasesbasesbases and the nonparallel sides are the
legslegslegslegs. Angles along one leg are
supplementary.
Note: a trapezoid whose legs are
congruent is called an isosceles trapezoidisosceles trapezoidisosceles trapezoidisosceles trapezoid.
>
>
base
base
leg leg
base angles
base angles
Isosceles Trapezoid Theorems
If a quadrilateral is an isosceles trapezoid,
then each pair of base angles is congruent.
If a trapezoid has one pair of congruent
base angles, then the trapezoid is
isosceles.
A trapezoid is isosceles if and only if its
diagonals are congruent.
>
>
T
R A
P
∠R ≅ ∠A, ∠T ≅ ∠P
TR AP≅
TA RP≅
Examples 1. Find the value of x.
5x = 40
x = 8
2. If NS=14 and BA=25, find SE.
SE = 25 — 14 = 11
140º
5xº
B E
AN
SSSS
40º
Trapezoid Midsegment Theorem
The midsegment of a trapezoid is parallel
to each base, and its length is one half
the sum of the lengths of the bases.
>
>
H
A
Y
F
V
R
AV HF, AV YR
( )
1
AV HF YR
2
= +
Examples is the midsegment of trapezoid OFIG.
1. If OF=22 and GI=30, find MY.
2. If OF=16 and MY=18, find GI.
>
>
O
M
G
F
Y
I
MY
( )
1
MY 22 30 26
2
= + =
( )
1
18 16 GI
2
= +
36 16 GI= +
GI 20=

2.7.5 Kites and Trapezoids

  • 1.
    2.7.5 Kites &Trapezoids The student is able to (I can): • Use properties of kites and trapezoids to solve problems
  • 2.
    kite A quadrilateralwith exactly two pairs of congruent consecutive nonparallel sides. Note: In order for a quadrilateral to be a kite, nononono sides can be parallel and opposite sides cannot be congruent.
  • 3.
    If a quadrilateralis a kite, then its diagonals are perpendicular. If a quadrilateral is a kite, then exactly one pair of opposite angles is congruent.
  • 4.
    Example In kiteNAVY, m∠YNA=54º and m∠VYX=52º. Find each measure. 1. m∠NVY 90 — 52 = 38º 2. m∠XYN 3. m∠NAV 63 + 52 = 115º N A V Y X − = = ° 180 54 126 63 2 2
  • 5.
    trapezoid A quadrilateralwith exactly one pair of parallel sides. The parallel sides are called basesbasesbasesbases and the nonparallel sides are the legslegslegslegs. Angles along one leg are supplementary. Note: a trapezoid whose legs are congruent is called an isosceles trapezoidisosceles trapezoidisosceles trapezoidisosceles trapezoid. > > base base leg leg base angles base angles
  • 6.
    Isosceles Trapezoid Theorems Ifa quadrilateral is an isosceles trapezoid, then each pair of base angles is congruent. If a trapezoid has one pair of congruent base angles, then the trapezoid is isosceles. A trapezoid is isosceles if and only if its diagonals are congruent. > > T R A P ∠R ≅ ∠A, ∠T ≅ ∠P TR AP≅ TA RP≅
  • 7.
    Examples 1. Findthe value of x. 5x = 40 x = 8 2. If NS=14 and BA=25, find SE. SE = 25 — 14 = 11 140º 5xº B E AN SSSS 40º
  • 8.
    Trapezoid Midsegment Theorem Themidsegment of a trapezoid is parallel to each base, and its length is one half the sum of the lengths of the bases. > > H A Y F V R AV HF, AV YR ( ) 1 AV HF YR 2 = +
  • 9.
    Examples is themidsegment of trapezoid OFIG. 1. If OF=22 and GI=30, find MY. 2. If OF=16 and MY=18, find GI. > > O M G F Y I MY ( ) 1 MY 22 30 26 2 = + = ( ) 1 18 16 GI 2 = + 36 16 GI= + GI 20=