MHB What is the distance AB across the lake using given data?

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The distance AB across the lake is calculated using the provided data, with AC measuring 400 meters and angle CAB at 40 degrees. The formula used is AB = 400 / Cos(40), resulting in a distance of approximately 522 meters. The calculation was confirmed as correct by other participants in the discussion. The problem was solved in a quick timeframe of five minutes. The final answer for the distance across the lake is 522 meters.
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Determine the distance AB across a lake using the following data: AC = 400 m, angle C = 90°, and angle CAB = 40°. Round the answer to the nearest meter.

Solution:

I say AB = 400/[Cos 40] = 522 meters

I then know the distance AB across the lake = 522 meters.

I timed myself for this one. I did it in 5 minutes.

Is any of this right?
 
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Yes, that is correct. Well done!
 
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