142 – 53 + x = 300
x = 300 + 53 – 142
x = 211
(102-х)×96=6048
раскроем скобки
9792-96x = 6048
-96x+3744 = 0
96x-3744 = 0
96x = 3744
x = 39
211+х×72=5179
х×72=5179-211
х×72=4968
х=4968/72
х=6,9
142 – 53 + x = 300
x = 300 + 53 – 142
x = 211
(102-х)×96=6048
раскроем скобки
9792-96x = 6048
-96x+3744 = 0
96x-3744 = 0
96x = 3744
x = 39
211+х×72=5179
х×72=5179-211
х×72=4968
х=4968/72
х=6,9