54*x+96=204,780: (x-7)=78 p.s для брата 15 не жалко

54*x+96=204,
54x=204-96
54x=108
x=108:54
x=2

780:(x-7)=78
x-7=780:78
x-7=10
x=10+7
x=17

54 • х + 96 = 204
54х = 204 – 96
54х = 108
х = 108 : 54
х = 2

780 : (х – 7) = 78
780 = 78(х – 7)
10 = х – 7
– х = – 7 – 10
– х = – 17
х = 17