Odpowiedź :
[tex]A=5x-y\\\\B=-3x-5y\\\\A-B=(5x-y)-(-3x-5y)=5x-y+3x+5y=8x+4y\\\\[/tex]
Natomiast:
[tex]-A+B=-[A-B]=-(8x+4y)=-8x-4y[/tex]
[tex]A = 5x-y \ \ oraz \ \ B = -3x-5y\\\\\\a) \ A-B = 5x-y-(-3x-5y) =5x-y+3x+5y = 8x+4y[/tex]
[tex]b) \ -A+B = -(5x-y)+(-3x-5y) = -5x+y -3x-5y = -8x-4y[/tex]