SOLUTION: please help me with this proof!! given- ab=3 bc= 2 ac=4 prove angle 1 is acute

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Question 253351: please help me with this proof!!

given-
ab=3 bc= 2 ac=4
prove angle 1 is acute

Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
given-
ab=3 bc= 2 ac=4
prove angle 1 is acute
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There's no way to know which is angle 1, but the angle opposite the side=4 will be the largest.
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Law of Cosines:
ac^2 = ab^2 + bc^2 - 2*ab*bc*cos(angle)
16 = 9 + 4 - 2*3*2*cos
-12cos = 3
cos = -1/4
angle =~ 104.5º
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That angle is not acute, the other 2 are.

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