A = 5,65 \(\times\) 13,8 + 35,7 \(\times\) 3,21 + 5,65 \(\times\) 21,9 + 35,7 \(\times\) 1,14
A = 5,65 \(\times\) (13,8 + 21,9) + 35,7 \(\times\) (3,21 + 1,14)
A = 5,65 \(\times\) 35,7 + 35,7 \(\times\) 4,35
A = (5,65 + 4,35) \(\times\) 35,7
A = 10 \(\times\) 35,7
A = 357
A=[5.65 x (13.8+21.9)]+[35.7 x (3.21+1.14)]
=[5.65 x 35.7]+[35.7 x 4.35]
=5.65 x 35.7 + 35.7 x 4.35
=35.7 x (5.65+4.35)
=35.7 x 10
=357
ta có:A=5.65 x 13.8 +35.7 x 3.21 +5.65 x 21.9+35.7 x 1.14
=5.65 x (13.8+21.9)+35.7 x (3.21+1.14)
=5.65 x 35.7+35.7 x 4.35
=(5.65+4.35) x 35.7
=10 x 35.7=357
A=5,65 x 13,8+35,7x3,21+5,65x21,9+35,7x1,14
A=5,65(13,8+21,9)+35,7(3,21+1,14)
A=5,65x35,7+35,7x4,35
A=35,7(5,65+4,35)
A=35,7x10
A=357