Respuesta :

Answer:

Step-by-step explanation:

hello :

-4+5|4x-4|=21

add 4 : 5|4x-4| = 25

divid by 5 :  |4x-4| = 5  means : 4x-4 = 5   or 4x-4 = -  5  

4x=9 or 4x =-1

x= 9/4 or x = - 1/4