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Number 37 is a review problem that's going to involve the law of cosines.
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We know all three sides of the triangle, but we need to go find the angles.
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Now what helps here in this case is that these two sides are congruent, so that means the opposite angles of those sides are going to be congruent as well.
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So we're only going to have to use law of cosines once this time because of that.
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So we're going to find angle c.
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First.
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So law of cosines, if we're finding c, states that we're going to do c squared equal two squared plus b squared minus two times eight times t times the cosine of angle c.
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So this entire time, this is going to be like our big variable that we're trying to get alone.
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And we're going to be able to plug in all of the other values.
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So c is three.
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So we're going to have three squared is equal to 2 squared plus 2 squared minus 2 times 2 times 2 times 2 times the cosine of c.
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So let's clean that up a little bit.
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3 squared is 9...