Question

уравнения (x+20)×45=3105 ; 57×(500-x)=11457

Answer 1

х+20=3105:45=69
х=69-20
х=49
500-х=11457:57=201
х=500-201
х=299

Answer 2

(х+20)*45=3105
х+20=3105/45
х+20=69
х=69-20
х=49
-------------------------
проверка
(49+20)*45=3105
3105=3105

57*(500-х)=11457
500-х=11457/57
500-х=201
х=500-201
х=299
---------------------------
проверка
57*(500-299)=11457
11457=11457