а) 2x*(2c+3y)+(x+2)*(x-y)
б) (y-4)*(y+4)+(y-3)^2

а) 2x*(2c+3y)+(x+2)*(x-y)=4cx+6xy+x²-st+2x-2y=4cx+5xy+x²+2x-2yб)(y-4)(y+4)+(y-3)²=y²-16+y²-6y+9=2y²-7-6y