Unfortunately you are incorrect. The answer is actually tan(y) = 20/21
The tangent of an angle is the ratio of the opposite and adjacent sides.
tan(angle) = opposite/adjacent
tan(K) = JL/LK
tan(y) = 20/21
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Side note: the tangent of angle x would be the reciprocal of this fraction since the opposite and adjacent sides swap when we move to angle J
tan(angle) = opposite/adjacent
tan(J) = LK/JL
tan(x) = 21/20
