原式=-27-[-5-(1/5)÷(4/5)×4]-27÷(9/4)×(-2/3)
=-27-(-5-1)+8
=-27+6+8
=-13
一直|x|=3,y^2=16,则x=-3或3,y=-4或4,则x+y={ 四种答案:1.-3-4=-7 2.-3+4=1 3.3-4=-1 4. 3+4=7
原式=-27-(-5- 1/5 × 5/4 × 4 )- 27 × 4/9 × 4/9 =-27-(-6)- 16/3 =-21 - 16/3 = - 79/3
|x|=3,y^2=16,则x=-3或3,y=-4或4,则x+y={ 四种答案:1.-3-4=-7 2.-3+4=1 3.3-4=-1 4. 3+4=7
改:原式=-27-(-5- 1/5 × 5/4 × 4 )- 27 × 4/9 × 4/9 + 4 × [ -4 ×(-1/9)]= -27-(-6)-16/3 + 16/9 = -21 - 32/9 = -24又5/9 (或 - 221/9)