1) 4(9+7x)+21=393
36+28х+21=393
28х=-57+393
28х=336
х=12
2) 36+90x=486
90x=450
x=5
3)70+5b+6b=158
11b=88
b=8
1) 4(9+7x)+21=393
36+28х+21=393
28х=-57+393
28х=336
х=12
2) 36+90x=486
90x=450
x=5
3)70+5b+6b=158
11b=88
b=8