Respuesta :

Answer:

  17

Step-by-step explanation:

Opposite sides of the parallelogram AB and CD are the same length, so ...

  5x +2 = 8x -7

  9 = 3x . . . . . . . . add 7-5x

  3 = x

  AB = 5x +2 = 5·3 +2

  AB = 17 = CD