A X 6 + 126 X 3 = 450
A x 6 + 378 = 450
A x 6 = 450 - 378
A x 6 = 72
A = 72 : 6
A = 12
Đúng 100 % lun cho mình nha
A x 6+126 x 3 = 450
=> A= 450 - 126 x 3
= 450-378
= 72
Vậy A= 72
A*6+126*3=450
A*6+378=450A*6=450-378
A*6=72
A=72/6
A=12
\(A.6+126.3=450\)
\(A.6+378=450\)
\(A.6\) \(=450-378\)
\(A.6\) \(=72\)
\(A=72:6\)
\(A=12\)
A x 6 + 126 x 3 = 450
A x 6 + +378 = 450
A x 6 = 72
A = 12
\(a\times6+126\times3=450.\)
\(a\times6+\left(63\times2\right)\times3=450\)
\(a\times6+63\times6=450\)
\(\left(a+63\right)\times6=450\)
\(a+63=450:6\)
\(a+63=75\)
\(a=75-63\)
\(a=12\)
Ax6+126x3=450
Ax6=450_(126x3)
Ax6=450_378
Ax6=72
A=72:6
A=12
vậy A=12