Question

4×(9+7x)+21=393 помогите пожалуста

Answer 1

36 + 28х + 21 = 393
28х + 57 = 393
28х = 393 - 57
28х = 336
   х = 12
  

Answer 2

4(9+7х)+21=393
36+28х+21=393
28х+57=393
28х=393-57
28х=336
х=336:28
х=12

4(9+7*12)+21=36+336+21=393
393=393