# Math

Given ABC with b = 21, c = 32, and mA 40° , find a. Round the cosine value to the nearest thousandth and answer to the nearest hundredth.
In this one I got 22.43

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1. a^2 = b^2 + c^2 - 2bc cosA
a^2 = 21^2 + 32^2 - 2*21*32*cos40°
a^2 = 435.4
a = 20.86

So, how did you get 22.43 ?

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2. Oh... I just checked and I did it wrong

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