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1. "The triangle ABC is such that AB=6cm, AC =12cm and angle BAC is obtuse. The area of the triangle ABC is 14 x the square root of 2. Find the size of the angle BAC" basically when I worked it out I got an angle of around 33 degrees but it states in the question the angle is obtuse. I can't seem to find where I've gone wrong though. I basically used the formula for the area of a triangle and plugged all the given information in. Any help would be appreciated

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2. (Original post by 001458nicole)
...
I presume you used the inverse sine to get that.

Don't forget x and 180-x both have the same sine value, and you're told the angle is obtuse.
3. Oh yes! Thank you very much makes much more sense now

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