Geometry in 3 Dimensions You can use three coordinates (x, y, z) to locate points in three dimensions.
-
Point P has coordinates
(
6
,
−
3
,
9
)
open 6 comma negative 3 comma 9 close as shown below. Give the coordinates of points A, B, C, D, E, F, and G.
Image Long Description
Distance in 3 Dimensions In a three-dimensional coordinate system, you can find the distance between two points
(
x
1
,
y
1
,
z
1
)
open , x sub 1 , comma , y sub 1 , comma , z sub 1 , close and
(
x
2
,
y
2
,
z
2
)
open , x sub 2 , comma , y sub 2 , comma , z sub 2 , close with this extension of the Distance Formula.
d
=
(
x
2
−
x
1
)
2
+
(
y
2
−
y
1
)
2
+
(
z
2
−
z
1
)
2
d equals . square root of open . x sub 2 , minus , x sub 1 . close squared . plus . open . y sub 2 , minus , y sub 1 . close squared . plus . open . z sub 2 , minus , z sub 1 . close squared end root
Find the distance between each pair of points to the nearest tenth.
-
P
(
2
,
3
,
4
)
,
Q
(
−
2
,
4
,
9
)
p open 2 comma 3 comma 4 close comma q open negative 2 comma 4 comma 9 close
-
T
(
0
,
12
,
15
)
,
V
(
−
8
,
20
,
12
)
t open 0 comma 12 comma 15 close comma v open negative 8 comma 20 comma 12 close
Standardized Test Prep
SAT/ACT
- A segment has endpoints
(
14
,
−
8
)
open 14 comma negative 8 close and (4, 12). What are the coordinates of its midpoint?
- (9, 10)
-
(
−
5
,
10
)
open negative 5 comma 10 close
-
(
5
,
−
10
)
open 5 comma negative 10 close
- (9, 2)
- Which of these is the first step in constructing a congruent segment?
- Draw a ray.
- Find the midpoint.
- Label two points.
- Measure the segment.
Short Response
- The midpoint of
R
S
¯
r s bar is
N
(
−
4
,
1
)
.
n open negative 4 comma 1 close . One endpoint is
S
(
0
,
−
7
)
.
s open 0 comma negative 7 close .
- What are the coordinates of R?
- What is the length of
R
S
¯
r s bar to the nearest tenth of a unit?
Mixed Review
See Lesson 1-6.
Use a straightedge and a compass.
- Draw
A
B
¯
.
eh b bar , . Construct
P
Q
¯
p q bar so that
P
Q
=
2
A
B
.
p q equals 2 eh b .
- Draw an acute
∠
RTS
.
angle Construct the bisector of
∠
RTS
.
angle
See Lesson 1-4.
Use the diagram below.
- Name
∠
1
angle 1 two other ways.
- If
m
∠
PQR
=
60
,
m angle what is
m
∠
RQS
?
m angle
Get Ready! To prepare for Lesson 1-8, do Exercises 69–72.
See p. 826.
Complete each statement. Use the conversion table on page 837.
-
130
in.
=
□
ft
130 , in. , equals white square ft
-
14
yd
=
□
in.
14 , yd equals white square , in.
-
27
ft
=
□
yd
27 , ft equals white square yd
-
2
mi
=
□
ft
2 mi equals white square ft