Respuesta :

Banabanana
MN is the  mid-line of a trapezoid HJLK.
The length of the mid-line of a trapezoid is half of the sum of the lengths of its bases ⇒

(KL + HJ)/2 = MN
(KL + 45)/2 = 28
KL + 45 = 28 * 2
KL + 45 = 56
KL = 56 - 45
KL = 11