如题所述
第1个回答 2014-07-17
1，=（3.6＋1.4)+(-1.9-10.1)
=5-12
=-7
2 , =(11+9)+(-7-13)
=20-20
=0
3, =(49,19/21+27,2/21)+(-78.21-21.79)
=77-100
=-23
=5-12
=-7
2 , =(11+9)+(-7-13)
=20-20
=0
3, =(49,19/21+27,2/21)+(-78.21-21.79)
=77-100
=-23
