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3 years ago

Answer please no work needed

Mathematics

1 answer:

lozanna [386]3 years ago

5 0

Answer: choice B
Angle A = 63 degrees
side a = 13.4
side b = 6.8

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Given Info:
Angle C = 90 degrees
Angle B = 27 degrees
side c = 15

What is needed to be found:
Angle A, side a, side b

Finding side a
cos(angle) = adjacent/hypotenuse
cos(B) = BC/AB
cos(B) = a/15
cos(27) = a/15
15*cos(27) = a
13.3650978628256 = a
a = 13.3650978628256
a = 13.4

Finding side b
Using the pythagorean theorem
a^2 + b^2 = c^2
(13.3650978628256)^2 + b^2 = 15^2
178.625840882906 + b^2 = 225
178.625840882906 + b^2 - 178.625840882906 = 225 - 178.625840882906
b^2 = 46.374159117094
sqrt(b^2) = sqrt(46.374159117094)
b = 6.809857496093
b = 6.8

Finding angle A
sin(angle) = opposite/hypotenuse
sin(A) = BC/AB
sin(A) = a/c
sin(A) = 13.3650978628256/15
sin(A) = 0.89100652418838
arcsin(sin(A)) = arcsin(0.89100652418838)
A = 63.0000000000016
A = 63

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