express sin A, cos A, and tan A as ratios
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Explanation:
Sine of an angle is the ratio of the opposite side over the hypotenuse. For reference angle A, the opposite side is BC = 6sqrt(3). The hypotenuse is the longest side AB = 12
Sin(angle) = opposite/hypotenuse
sin(A) = BC/AB
sin(A) = 6sqrt(3)/12
sin(A) = sqrt(3)/2
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Cosine is the ratio of the adjacent and hypotenuse
cos(angle) = adjacent/hypotenuse
cos(A) = AC/AB
cos(A) = 6/12
cos(A) = 1/2
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Tangent is the ratio of the opposite and adjacent
tan(angle) = opposite/adjacent
tan(A) = BC/AC
tan(A) = 6sqrt(3)/6
tan(A) = sqrt(3)