D=57.(49-19)-57.(24+49)
<=>D=57.30-57.73
<=>D=57.(30-73)
<=>D=57.(-43)
<=>D=-2451
D=57.(49-19)-57.(24+49)
=57.(49-19-24-49)
=57.(-33)
=1881
Học tốt!
SD W 843=838
57.(49-19)-57.(24+49)
=57.[(49-19)-(24+49)]
=57.(-43)
=-2451
D=57.(49-19)-57.(24+49)
=0