Answer:
(C) 22°
Explanation:
You want the measure of angle 4 in the rhombus shown.
Triangles
The diagonals of a rhombus divide the figure into congruent right triangles. The acute angles in each of those triangles are complementary, so we have ...
∠4 +68° = 90°
∠4 = 22° . . . . . . . . subtract 68°
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Additional comment
The diagonals cross at right angles, so ...
∠1 = ∠5 = 90°
The angles at the ends of the diagonals are congruent, so ...
∠2 = ∠6 = 68°
∠3 = ∠4 = 22°