(x+1)(x-1)+(x+1)^2+(x+1)^2-3x(x+1)=0
x^2-1^1+2(x^2+2x+1)-3x^2-3x=0
x^2-1+2x^2+4x+2-3x^2-3x=0
x+1=0
x=-1
…
-(1-2x)^2=2(5x^2+4)+(2x-3)(2x+3)-2(3x-1)^2
-(1-4x+4x^2)=10x^2+8+4x^2-9-2(9x^2-6x+1)
-1+4x-4x^2=10x^2+8+4x^2-9-18x^2+12x-2
-1+4x-4x^2-10x^2-8-4x^2+9+18x^2-12x+2=0
-8x+2=0
-8x=-2
x=\frac{1}{4}
…
(2y+3)^2-5(2y^2-3^2)-(y-2)-(2y+1)^2
4y^2+12y+9-10y^2+45-y+2+1=-2y^2-4y-(4y^2+4y+1)
-6y^2+11y+57=-2y^2-4y-4y^2-4y-1
-6y^2+11y+57+6y^2+8y+1=0
19y+58=0
19y=-58
y=-3\frac{1}{19}
…
-(x-1)^2+(x-2)(x+2)=-(2x-2)^2+4(x^2-2)
-(x^2-2x+1)+x^2-4=-(4x^2-4x+1)+4x^2-8
-x^2+2x-1+x^2-4=-4x^2+4x-1+4x^2-8
2x-5-4x+9=0
-2x+4=0
-2x=-4
x=2
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