n²-m²+3n-3m = (n+m)(n-m)+(3)(n-m) = (n+m+3)(n-m)4s²+10s-5y-y² = (4s-y)(s+y)+(5)(s+y) = (4s-y+5)(s+y)x²-4x²y+4y²+y = (x²+4y²)+(1-4xy) = (x²+4y²)+(1-y)(1+4x)2r-1-t+2rt = (2r-t)-(1-2rt) = (2r-t)+(2rt-1) = (2r+1)(1+t)2x-1-y+2xy = (2x-1)+(2xy-y) = (2x-1)+(2x)(y-1) = (2x-1)(1+2x)1+3g+2j+3gj+j² = (1+2j)+(3g+3gj+j²) = (1+2j)+g(3+3j+j) = (1+2j+g)(1+3j)