-
Use the diagram below. Find the coordinates of the given point.
-
A
′
,
eh prime comma the reflection image of A across
y
=
x
y equals x
-
A
″
,
eh double prime comma the reflection image of
A
′
eh prime across
y
=
−
x
y equals , negative x
-
A
‴
,
eh triple prime comma the reflection image of
A
″
eh double prime across
y
=
x
y equals x
-
A
″
″
,
eh double prime double prime comma the reflection image of
A
‴
eh triple prime across
y
=
−
x
y equals , negative x
- How are A and
A
″
″
eh double prime double prime related?
C Challenge
Reasoning Can you form the given type of quadrilateral by drawing a triangle and then reflecting one or more times? Explain.
- parallelogram
- isosceles trapezoid
- kite
- rhombus
- rectangle
- square
-
Coordinate Geometry Show that B(b, a) is the reflection image of A(a, b) across the line
y
=
x
.
y equals x . (Hint: Show that
y
=
x
y equals x is the perpendicular bisector of
A
B
¯
.
eh b bar , . )
Standardized Test Prep
SAT/ACT
- What is the reflection image of (a, b) across the line
y
=
−
6
?
y equals . negative 6 question mark
-
(
a
−
6
,
b
)
open eh minus 6 comma b close
-
(
a
,
b
−
6
)
open eh comma b minus 6 close
-
(
−
12
−
a
,
b
)
open minus . 12 minus eh comma b close
-
(
a
,
−
12
−
b
)
open eh comma minus . 12 minus b close
- The diagonals of a quadrilateral are perpendicular and bisect each other. What is the most precise name for the quadrilateral?
- rectangle
- parallelogram
- rhombus
- kite
-
A
D
→
eh d vector bisects
∠
A
angle eh of
Δ
C
A
B
,
cap delta c eh b comma with point D on
C
B
¯
.
c b bar , . Which of the following is true?
-
C
D
D
B
=
C
A
B
A
fraction c d , over d b end fraction . equals . fraction c eh , over b eh end fraction
-
C
D
D
B
=
B
A
C
A
fraction c d , over d b end fraction . equals . fraction b eh , over c eh end fraction
-
C
B
C
D
=
C
A
B
A
fraction c b , over c d end fraction . equals . fraction c eh , over b eh end fraction
-
C
A
C
B
=
A
B
D
B
fraction c eh , over c b end fraction . equals . fraction eh b , over d b end fraction
Extended Response
- Write an indirect proof of the following statement: The hypotenuse of a right triangle is the longest side of the right triangle.
Mixed Review
For the given points,
A
′
B
′
¯
eh prime , b prime bar is a translation of
A
B
¯
.
eh b bar , . Write a rule to describe each translation.
See Lesson 9-1.
-
A
(
−
1
,
5
)
,
B
(
2
,
0
)
,
A
′
(
3
,
3
)
,
B
′
(
6
,
−
2
)
eh open negative 1 comma 5 close comma b open 2 comma 0 close comma , eh prime , open 3 comma 3 close comma , b prime , open 6 comma negative 2 close
-
A
(
−
9
,
−
4
)
,
B
(
−
7
,
1
)
,
A
′
(
−
4
,
−
3
)
,
B
′
(
−
2
,
2
)
eh open negative 9 comma negative 4 close comma b open negative 7 comma 1 close comma , eh prime , open negative 4 comma negative 3 close comma , b prime , open negative 2 comma 2 close
See Lesson 7-2.
-
Maps A map of Alberta, Canada, uses the scale
1
cm
=
25
km
.
1 cm equals 25 , km . On the map, the distance from Calgary to Edmonton is 11.1 cm. How far apart are the two cities?
Get Ready! To prepare for Lesson 9-3, do Exercises 58–63.
See p. 824.
Use a protractor to draw an angle with the given measure.
-
120
°
120 degrees
-
90
°
90 degrees
-
72
°
72 degrees
-
60
°
60 degrees
-
45
°
45 degrees
-
36
°
36 degrees