Răspuns :
2(2x+19) + 90 = 180
4x + 38 +90 = 180
4x + 128 =180
4x = 180-128
4x = 52
x= 52/4
x=13
4x + 38 +90 = 180
4x + 128 =180
4x = 180-128
4x = 52
x= 52/4
x=13