Trigonometry of Right Triangles - California State University, Los
9.1 – 9.3 Solving Right Triangles without Trigonometry.
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Transcript of 9.1 – 9.3 Solving Right Triangles without Trigonometry.
9.1 – 9.3 Solving Right Triangles without Trigonometry
2. Find the length of the altitude drawn to the hypotenuse.
158
x
a) x = 10.95
b) x = 11.5
c) x = 13.56
d) None of the above
<Explanation follows.>
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2. Solution
158
x You can redraw the triangles:
B
A
C D
C
BD
A
C8
x
x
1523
15
x
x
8
So,
x2 = 8*15
x2 = 120
x = 10.95 (A)
3. Find the value of x.
194
x
a) x = 219
b) x = 437
c) x = 223
d) x = 23
<Explanation follows.>
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3. Solution
You can redraw the triangles:
B
A
C D
C
BD
A
C4
xx 1923
23
x
x
19
So,
x2 = 19*23
x2 = 437
x = 437
194
x
19
4. The geometric mean of 5 and 15 is:
a) 3
b) 10
c) 5 3d) 75
<Explanation follows.>
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4. Solution
Geometric mean:
15
x
x
5
So,
x2 = 75
x = 75
x = 253
x = 53
9. Find the value of x.
a) 8.3
b) 7.0
c) 10.1
d) 1.9
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10. Choose the sets that are possible side lengths of a right triangle.
a) 1,1,2
b) 1,1,2c) 3,4,7
d) 3,4,5
e) a and c
f) b and d
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10.A. Find the side length of a square with a diagonal of length 10.
10
a) 3
b) 4.5
c) 7.07
d) 9
<Explanation follows.>
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10.A. Solution
So,
x2 + x2 = 100
2x2 = 100
x2 = 50
x = 7.07
10x
x
15. Find the value of h.
10
6h
11.6
a) h = 3.5
b) h = 5.1
c) h = 7.5
d) h = 10.77
<Explanation follows.>
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15. Solution
You can redraw the triangles:
B
A
C D
C
BD
A
C
h1010
h
11.6
h
10
6
11.6
10
6h
11.6
6
6
h
6
10
11.6
11. Which statements are true about options B and C in #11?
a) B is acute and C is obtuse
b) B is obtuse and C is acute
c) B is acute and C is not a triangle
d) B is obtuse and C is not a triangle
<Explanation follows.>
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11. SolutionB.6,7,12
C.20.8, 39, 74.2
Put the largest first and confirm it can be a triangle.
If yes, square them and compare largest to other two:
B. 122 _____ 62 + 72
144______ 36 + 49
C. 74.2______20.8 + 39
13. Find the value of x.
127
x
a) x = 257
b) x = 133
c) x = 19
d) x = 221
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