I just read about the cosine law and the sine law.(adsbygoogle = window.adsbygoogle || []).push({});

I have a practise problem and know to use the cosine law but what ever answer I get gives me a math error in my calculator.

the sides are a=4.3 b=5.2 c=7.5 I need to solve the triangle so find the 3 angles within.

[tex] a^2=b^2+c^2-2bc cos(A)\longrightarrow

18.49=27.04+56.25-78 cos(A) [/tex]

I tried bringing everything to the left side with the exception of cos(A) and then doing [tex] cos^-1 [/tex] but it just wont work in my calculator I keep getting a math error.

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# Homework Help: Trig Problem

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