2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 x 10
= 2 x 9 + 2 x 10
= 2 x ( 9 + 10 )
= 2 x 19
= 38
2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 x 10
= (2 x 9 )+ (2 x 10 )
= 2 x ( 9 + 10 )
=2 x 19
=38
2+2+2+2+2+2+2+2+2+2x10
18 + 20
38
hok tốt
\(2+2+2+2+2+2+2+2+2+2.10\)
\(=2+2+2+2+2+2+2+2+2+20\)
\(=4+2+2+2+2+2+2+2+20\)
\(=6+2+2+2+2+2+2+20\)
\(=8+2+2+2+2+2+20\)
\(=10+2+2+2+2+20\)
\(=12+2+2+2+20\)
\(=14+2+2+20\)
\(=16+2+20\)
\(=18+20\)
\(=38\)
2+2+2+2+2+2+2+2+2+2x10
=2x9+2x10
=2x(9+10)
=2x19=38
2+2+2+2+2+2+2+2+2+2x10
= 38
hok tốt nha
#vanh#