Aidez-moi please, les maths me tuent ^^

((2x-30)*3 -54)*4)-72=48
((6x-90-54)*4)-72=48
((6x-144)*4)-72=48
4x-576-72=48
4x-648=48
4x =48+648
4x =696
x =696/4
x= 174