Respuesta :

-|20| + |5| = -15

Steps:
Apply absolute rule: |a| = a, a >/ 0
|20| = 20
= -20+5
Apply absolute rule: |a| = a, a >/ 0
|5| = 5
= -20+5
Refine 
= -15

Hope this helps you! (:
-Hamilton1757