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

Thread starter xyz_1965
Start date Jul 29, 2020
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Lake

AI Thread Summary

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.

Jul 29, 2020

xyz_1965

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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Aug 12, 2020

HOI

Yes, that is correct. Well done!

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