Question

B(X,Y)=(a+b)x-(a+b)Y-a-b INDICA UN FACTOR PRIMO

Answer 1

B(X,Y)=(a+b)x-(a+b)y-a-b=
B(X,Y)=x(a+b)-y(a+b)-(a+b)=
B(X,Y)=(a+b)(x-y-1)