7-(3+x)-4x=4x-57
7 – 3 – x – 4x = 4x – 57
– x – 4x – 4x = – 57 + 3 – 7
-9x = -61
x = -61/-9
х=6,77777777778
7-(3+x)-4x=4x-57
7 – 3 – x – 4x = 4x – 57
– x – 4x – 4x = – 57 + 3 – 7
-9x = -61
x = -61/-9
х=6,77777777778