( x - 105) : 21 = 15
x - 105 = 315
x = 420
( x - 105 ) : 21 = 15
( x - 105 ) = 15 x 21
( x - 105 ) = 315
x = 315 + 105
x = 420
\(\left(x-105\right):21=15\)
\(x-105=15\times21\)
\(x-105=315\)
\(x=315+105\)
\(x=420\)
( x - 105 ) : 21 = 25
x - 105 = 21 . 25
x - 105 = 525
x = 525 + 105
x = 630
nha bn
mik đầu tiên đó
( x - 105 ) : 21 = 15
( x - 105 ) = 15 x 21
( x - 105 ) = 315
x = 315 + 105
x = 402
[x-105]:21=15
x-105=15x21
x-105=315
x=315+105
x=420
Nhầk
( x - 105 ) : 21 = 15
( x - 105 ) = 15 x 21
( x - 105 ) = 315
x = 315 + 105
x = 320
( x - 105 ) : 21 = 15
( x - 105 ) = 15 x 21
x - 105 = 315
x = 315 + 105
x = 420
Vậy x = 420