计算.(-5)×(-87/9)-(-7)×(+79/9)+12÷(-9/79)

问题描述:

计算.(-5)×(-87/9)-(-7)×(+79/9)+12÷(-9/79)
不好意思,问题弄错了应该是(-5)×(-79/9)-(-7)×(+79/9)+12÷(-9/79)

(-5)×(-87/9)-(-7)×(+79/9)+12÷(-9/79)
=5×87/9+7×79/9-12×79/9
=5×87/9+79/9*(7-12)
=5×87/9-5×79/9
=5/9×(87-79)
=5/9×8
=40/9不好意思,问题弄错了应该是(-5)×(-79/9)-(-7)×(+79/9)+12÷(-9/79)(-5)×(-79/9)-(-7)×(+79/9)+12÷(-9/79)=5×79/9+7×79/9-12×79/9=79/9*(5+7-12)=79/9*0=0