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Math Help - can someone help please

  1. #1
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    can someone help please

    My calulator is broken and I need this tomorrow. In triangle abc, a=7, b=9 and c=11. Find the three angle measures of the triangle. Using sin
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  2. #2
    is up to his old tricks again! Jhevon's Avatar
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    Quote Originally Posted by jwein4492 View Post
    My calulator is broken and I need this tomorrow. In triangle abc, a=7, b=9 and c=11. Find the three angle measures of the triangle. Using sin
    using sin what? you cannot use the law of sines here. and this is not a right triangle, so Pythagoras or trig ratios won't help us. use the law of cosines.

    a^2 = b^2 + c^2 - 2bc \cos A

    you can use that to find angle A. Similar formulas can get you angles B and C. Or, once you have angle A, you can use the law of Sines to get the other angles. Your choice
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