Respuesta :

bcalle
-4x +12 -12 = -4 -12
-4x = -16
x = 4
apologiabiology
times both sides by -1
4x-12=4
add 12 to both sides
4x+12-12=4+12
4x+0=16
4x=16
divide both sides by 4
(4x)/4=16/4
(4/4)x=4
1x=4
x=4