Odpowiedź:
[tex]g)\ \ -(4a+9b-6)-(a+5b-8)=-4a-9b+6-a-5b+8=-5a-14b+14\\\\\\h)\ \ -(x-y)-(2x-6y+7)+(3x-4y)=-x+y-2x+6y-7+3x-4y=3y-7\\\\\\i)\ \ -5(x+2x^2-3)-\frac{12x^2+9x-18}{3}=-5x-10x^2+15-(4x^2+3x-6)=\\\\=-5x-10x^2+15-4x^2-3x+6=-14x^2-8x+21\\\\\\j)\ \ (x+1)(x-7)+(8+x)(x-2)=x^2-7x+x-7+(8x-16+x^2-2x)=\\\\=x^2-6x-7+8x-16+x^2-2x=2x^2-23\\\\\\k)\ \ 3x(5y-x)+3(x+2y)(x-2y)-(2x+3y)^2=\\\\=15xy-3x^2+3(x^2-4y^2)-(4x^2+12xy+9y^2)=\\\\=15xy-3x^2+3x^2-12y^2-4x^2-12xy-9y^2=3xy-4x^2-21y^2[/tex]
[tex]l)\ \ -7(-9x+4y)+(8x-4y):(-4)=63x-28y+(-2x+y)=63x-28y-2x+y=\\\\=61x-27y\\\\\\l)\ \ (2x+3)^2+(2x-3)(2x+3)+(2x-3)^2=4x^2+12x+9+4x^2-9+4x^2-12x+9=\\\\=12x^2+9[/tex]
