-
- In the diagram,
c
=
x
+
y
.
c equals , x plus , y . Use Corollary 2 to Theorem 7-3 to write two more equations involving a, b, c, x, and y.
- The equations in part (a) form a system of three equations in five variables. Reduce the system to one equation in three variables by eliminating x and y.
-
State in words what the one resulting equation tells you.
-
proof Given: In right
△
A
B
C
,
B
D
¯
⊥
A
C
¯
,
and
D
E
¯
⊥
B
C
¯
.
white up pointing triangle eh b c comma , b d bar , up tack , eh c bar , comma , and . d e bar , up tack , b c bar , .
Prove:
A
D
D
C
=
B
E
E
C
fraction eh d , over d c end fraction . equals . fraction b e , over e c end fraction
Standardized Test Prep
SAT/ACT
- The altitude to the hypotenuse of a right triangle divides the hypotenuse into segments of lengths 5 and 15. What is the length of the altitude?
- 3
-
5
3
5 square root of 3
- 10
-
5
5
5 square root of 5
- A triangle has side lengths 3 in., 4 in., and 6 in. The longest side of a similar triangle is 15 in. What is the length of the shortest side of the similar triangle?
- 1 in.
- 1.2 in.
- 7.5 in.
- 10 in.
Short Response
- Two students disagree about the measures of angles in a kite. They know that two angles measure 124 and 38. But they get different answers for the other two angles. Can they both be correct? Explain.
Mixed Review
See Lesson 7-3.
- Write a similarity statement for the two triangles. How do you know they are similar?
See Lesson 6-2.
Algebra Find the values of x and y in
▱
R
S
T
V
.
white parallelogram r s t v .
-
R
P
=
2
x
,
P
T
=
y
+
2
,
V
P
=
y
,
P
S
=
x
+
3
r p . equals 2 x comma p t , equals y plus 2 , comma v p equals y comma p s , equals x plus 3
-
R
V
=
2
x
+
3
,
V
T
=
5
x
,
T
S
=
y
+
5
,
S
R
=
4
y
−
1
r v equals , 2 x plus 3 , comma v t , equals 5 , x comma t s equals , y plus 5 , comma s r equals , 4 y minus 1
Get Ready! To prepare for Lesson 7-5, do Exercises 54–56.
See Lesson 7-2.
The two triangles in each diagram are similar. Find the value of x in each.
-
-
-