Х-80=280+2 64-х=91:7 х+49=4528*4
х-80=282 64-х=13 х+49=18.112
х=282+80 х=64-13 х=18.112-49
х=362 х=51 х=18.063
---------------------- ------------ -----------------
362-80=280+2 64-51=91:7 18.063+49=4528*4
282=282 13=13 18.112=18.112
55+х=4.352-2.398 х-85=350+150 600-х=802:2
55+х=1.954 х-85=500 600-х=401
х=1.954-55 х=500+85 х=600-401
х=1.899 х=585 х=199
-------------------- ----------------- --------------
55+1.899=4.352-2.398 585-85=350+150 600-х=802:2
1.954=1.954 500=500 401=401
х+57=7.146*6 789+х=6.342-699
х+57=42.876 789+х=5.643
х=42.876-57 х=5.643-789
х=42.819 х=4.854
-------------------- -------------------
42.819+57=7.146*6 789+4.854=6.342-699
42.876=42.876 5.643=5.643