1. x^3+3x^2+3x+1-(x^3-3x^2+3x-1)=6x^2+2x
x^3+3x^2+3x+1-x^3+3x^2-3x+1=6x^2+2x
6x^2+2=6x^2=2x
2=2x
x=1
2. x^2+8x+16-x^2+4=0
8x+20=0
8x=-20
x=-5/2
3. 4x^2-20x+25-4x^2+9=0
-20x+34=0
-20x=-34
x=17/10
4. 9x^2-25-9x^2+6x-1=10
-26+6x=10
6x=10+26
6x=36
x=6
5. 2(4x^2+4x+1)-8(x^2-1)=34
8x^2+8x+2-8x^2+8=34
8x+10=34
8x=24
x=3
6. x^3-6x^2+12x-8-3x^2-4=x^3-9x^2+27x-27
-6x^2+12x-8-3x^2-4=-9x^2+27x-27
12x-12=27x-27
12x-27x=-27+12
-15x=-15
x=1
7. x63+6x^2=12x+8-(x^3-3x^2+3x-1)=9x^2=36
x^3+6x^2+12x+8-x^3-3x+1=9x^2+36
9x^2+9x+9=9x^2+36
9x+9=36
9x=27
x=3
8. x^3+9x^2+27=x^3+9x^2
27x+27=0
27x=-27
x=-1
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