-х^2+4=0
-x^2=0-4
-x^2=-4
x=-4:(-2)
х=2
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<span>1) с(х-3)-d(х-3) = (x-3)(c-d)
2) m(р-k)-(р-к) = (p-k)(m-1)
3) m(х-у)-n(у-х) = (x-y)(m+n)
4) х(2-х)+4(х-2) = (2-x)(x-4)
5) 4x(2x-y)-5y(y-2x) = (2x-y)(4x+5y)
6) (y+1)^2-4y(y+1) = (y+1)(y+1-4y) = (y+1)(1-3y)</span>