Question

решите уравнение 1) 4(9+7x)+21=393 2) 486:(5x+2)=18 3) 5(14+b)+6b=158

Answer 1

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

5(14+в)+6в=158
70+5в+6в=158
11в=158-70
11в=88
в=88/11
в=8