Zamień sumę na iloczyn:   a) 2y(x+y)-y-x b) x(x-1)-2(1-x) c) [latex](x+y)^{2}[/latex] +2(x+y) d) [latex](x^{2}+y^{2})-x^{2}(x^{2}+y^{2})[/latex] e) a(a-1)-4(1-a) f) 3z(x-5)+(5-x) g) 3b(b-4)-(4-b) h) 5(x-7)+10y(7-x) i) 3(x+y)+([latex](x+y)^{2}[/latex]

Zamień sumę na iloczyn: a) 2y(x+y)-y-x = = 2y(x +y) -1( x +y) = = (x +y)( 2y -1)   b) x(x-1)-2(1-x) = = - x (1 -x) -2( 1 -x) = = (1-x)( -x -2) = = -(1-x)( x +2)   c) +2(x+y)= = (x +y) ( x +y +2) =   d)  = =(x² +y²) ( 1 -x²) = = (x² +y²) ( 1-x)(1+x)   e) a(a-1)-4(1-a)= = a(a -1) +4(a -1) = (a -1)( a +4)   f) 3z(x-5)+(5-x)= = 3z(x-5) -1( x -5) = = (x -5)(3z -1)   g) 3b(b-4)-(4-b)= = 3b(b -4) + 1(b -4) h) 5(x-7)+10y(7-x)= = (7 -x)( 5 +10y) = = 5( 1 +2y)(7 -x)   i) 3(x+y)+( = = (x +y)( 3 + x + y)