a)-5x(2-y)-y(5x+1)+10x(-y+1)= b)3x(2xy-y)= c)-3(3-2xy+5y)= d)-4a(-5a+5ab-3b)=
źródło:
a) -5x(2-y)-y(5x+1)+10x(-y+1)= -10x+5xy -5xy -y -10xy +10x= -y-10xy
b) 3x(2xy-y)= 6$x^2$y - 3xy
c) -3(3-2xy+5y)= -9+6xy-15y= (uporządkuję) -15y+6xy-9
d) -4a(-5a+5ab-3b)= 20$a^2$ -20$a^2$b +12ab