9514 1404 393
Answer:
68°
Explanation:
Alternate interior angles are congruent, so we have ...
123° = d° +55°
d = 123 -55 = 68
Angle D measures 68°.
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For those of you inclined to use this answer for other questions, here are the other angles in this figure.
A = 55° . . . . alternate interior with 55°, so congruent
B = C = 180° -123°
B = C = 57°