y(y-5)•(y+5)-(y+2)•(y²-2y+4)

y(y-5)•(y+5)-(y+2)•(y²-2y+4)у•(у²-25)-(у+2)•(у²-4)у³-25у-у³-4у+2у²-8-29у+2у²-8=02у²-29у-8=0Д=в²-4асД=841-4•2•(-8)=841+64=