А) (a - 86) *204 = 7548
204a - 17544 = 7548
204a = 7548 +17544
204a = 25092
a = 25092:204
a = 123
б) a:70 - 912 = 304*3
a:70 - 912 = 912
a:70 = 912 +912
a:70 = 1824
a = 1824*70
a = 127680
в) 38 * b +69 = 3945
38b = 3945-69
38b = 3876
b = 3876 : 38
b = 102
г) 17487 : (x +56) = 87
x + 56 = 17487 : 87
x + 56 = 201
x = 201 - 56
x = 145
д) a :69 - 754 = 48
a : 69 = 48+754
a: 69 = 802
a = 802 * 69
a = 55338
е) (4118 - x) : 68 = 56
4118 - x = 56*68
4118 - x = 3808
x=4118-3808
x= 310
ж) 49*x-17301=12050
49x=12050+17301
49x=29351
x=29351:49
x=599
з)40000-54x=7492
54x=40000-7492
54x=32508
x=32508:54
x=602