有理数加法,9+(-2) (-9)+2-9+05+(-22)(-1.3)+(-8)(-0.9)+1.52.7+(-3.5)(-3)+(-9)(-3)+(+9)
网友回答
9+(-2)=9-2=7
(-9)+2
=-(9-2)=-7-9+0=-9
5+(-22)
=-(22-5)=-17(-1.3)+(-8)
=-(1.3+8)=-2.1(-0.9)+1.5
=(1.5-0.9)=0.62.7+(-3.5)
=-(3.5-2.7)=-0.8(-3)+(-9)
=-(3+9)=-12(-3)+(+9)
=9-3=6======以下答案可供参考======
供参考答案1:
9+(-2)
=9-2 =7 (-9)+2
=-7 -9+0=-9 5+(-22)
=-17 (-1.3)+(-8)
=-1.3-8
=-9.3 (-0.9)+1.5
=1.5-0.9
=0.6 2.7+(-3.5)
=2.7-3.5
=-0.8 -3+(-9)
=-3-9 =-12 -3+9 =6