-2x-{4x-2y-[3x-(2x+1)]-10},其中x=-3,y=2009

问题描述:

-2x-{4x-2y-[3x-(2x+1)]-10},其中x=-3,y=2009

-2x-{4x-2y-[3x-(2x+1)]-10}
=-2x-4x+2y+[3x-(2x+1)]+10
=-2x-4x+2y+3x-(2x+1)+10
=-2x-4x+2y+3x-2x-1+10
=-5x+2y+9

当x=-3, y=2009时,
原式=-5×(-3)+2×2009+9
=15+4018+9
=4042

-2x-{4x-2y-[3x-(2x+1)]-10}
=-2x-{4x-2y-[3x-2x-1]-10}
=-2x-{4x-2y-3x+2x+1-10}
=-2x-{3x-2y-9}
=-2x-3x+2y+9
=-5x+2y+9
当x=-3, y=2009时
原式=-5*(-3)+2*2009+9
=4042

-2x-{4x-2y-[3x-2x-1]-10}
=-2x-{4x-2y-x+1-10}
=-2x-{3x-2y-9}
=-2x-3x+2y+9
=-5x+2y+9
将x=-3,y=2009代入上述代数式,得出答案4042

原式=-2x-4x+2y+[3x-(2x+1)]+10
=-6x+2y+3x-(2x+1)+10
=-3x+2y-2x-1+10
=-5x+2y+9
=15+4018+9
=4042

-2x-{4x-2y-[3x-(2x+1)]-10}
=-2x-{4x-2y-3x+2x+1-10}
=-2x-4x+2y+3x-2x-1+10
=-5x+2y+9
=-5*(-3)+2*2009+9
=4018+24
=4042

-2x-{4x-2y-[3x-(2x+1)]-10}
=-2x-{4x-2y-[x-1]-10}
=-2x-{4x-2y-x+1-10}
=2x-4x+2y+x-1+10
=-x+2y+9
=3+4018+9
=5030