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3 years ago

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Points A and B are separated by a lake. To find the distance between them, a surveyor locates a point C on land such that CAB =

48.6°. He also measures CA as 310 ft and CB as 527 ft. Find the distance between A and B. Round your answer to the nearest foot. (Note: ABC is an acute angle.)

1 answer:

nikklg [1K]3 years ago

7 0

Use the Law of Cosine
$c^2=a^2+b^2-2ab\cos{\gamma}$

$527^2=310^2+AB^2-2\times310\times AB\times\cos{48.6^o}
\\AB^2-410\times AB-181,629=0
\\
\\AB= \frac{410+ \sqrt{410^2-4(-181629)} }{2} =678$

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