In a rhombus, the opposite angles are equal. So if one angle is 54 degrees and the opposite angle is the same,, you have 54 + 54 = 108. All of the angles in a rhombus always add up to a total of 180 degrees, so subtract 108 from 180 to get 72 degrees. This means that the other two angles add up to 72, and since we know that opposite angles are equal, we divide 72 by 2 to get 36. This means that the measure of the angle that is adjacent to the 54 degree angle is 72 degrees.
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