3x²y-﹛xyz-﹙2xyz-x²z﹚-4x²z+[3x²y-﹙4xyz-5x²z-3xyz﹚]﹜
=3x²y-﹛xyz-2xyz+x²z-4x²z+[3x²y-4xyz-5x²z-3xyz]﹜
= 3x²y-﹛xyz-2xyz+x²z-4x²z+3x²y-4xyz-5x²z-3xyz﹜
=3x²y-xyz+2xyz-x²z+4x²z-3x²y+4xyz+5x²z+3xyz
=(3x²y-3x²y)+(2xyz-xyz+4xyz+3xyz)+ (4x²z-x²z+5x²z)
=8+8xyz+8x²z