Respuesta :

9514 1404 393

Answer:

  68°

Step-by-step 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°