Решите уравнения: 1) 15х-7х-99=797 2) (287+у)*39=15678 * - знак умножить всем заранее !

1) 15х-7х-99=797
8х=797+99
8х=896
х=896:8
х=112

2) (287+у)*39=15678
11193+39у=15678
39у=15678-11193
39у=4485
у=4485:39
у=115

2) (287+y)*39=15678                                                                                                   
 287+y=15678:39                                                                                                    
 287+y=402                  
y=402-287                    
y=115
1) 15х-7х-99=797
8х=797+99
8х=896
х=896:8
х=112