Answer:
Step-by-step explanation:
Corresponding sides of these triangles are proportional, so you have ...
x/5 = 20/x
x² = 5·20 . . . . . . . cross multiply
x = √100 = 10
and ...
y/15 = 5/y
y² = 15·5 . . . . . . cross multiply
y = √75 ≈ 8.7
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For more on the subject, see ...
brainly.com/question/26276659
Cos x = -12/13
sin x = -sqrt(13^2 - 12^2) / 13 = -5/13
tan x = 5/12
tan x/2 = (1 - cos x) / sin x = 1 - (-12/13) / -5/13 = 25/13 * -13/5 = -5
2sin^2 x/2 = 1 - cos x = 1 - (-12/13) = 25/13
sin^2 x/2 = 25/13 / 2 = 25/26
sin x/2 = 5/√26
sin x/2 / cos x/2 = tan x/2
cos x/2 = sin x/2 / tan x/2 = 5/√26 / -5 = -1/√26
sin x/2 = 5/√26
cos x/2 = -1/√26
tan x/2 = -5
The simplified mathematical expressions with the first factor to the nearest tenth are:
7.8 x 10
3.3 x 
2.1 x 
3.7
<h3>What are the
simplified mathematical expressions ?</h3>
Scientific notation is used to simplify large numbers in smaller numbers. In order to write a number in scientific notation , the number is written as a decimal number, between 1 and 10 and multiplied by a power of 10.
(8.6 x
) . (9.1 x
)
= (8.6 x 9.1) x
= 78.26 x
= 7.8 x 10
(6.9 x
) . (4.8 x
)
= 33.12 x 
3.3 x 
(3.7 x
) . (4.6 x
) ÷ (1.4 x
) . (5.7 x
)
= 1.7 x 10 ÷ 8 x10²
0.21 x 
2.1 x 
(3.1 x
) . (5.3 x
) ÷ (7.3 x
) . (6.1 x
) = 3.7
To learn more about scientific notation, please check: brainly.com/question/25334755
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