`1)``(-8x^{5}+12x^{3}-16x^{2}):4x^{2}` `=-2x^{3}+3x-4`
`2)``(12x^{3}y^{3}-18x^{2}y+9xy^{2}):6xy` `=2x^{2}y^{2}-3x+3/2y`
`3)``(-7x^{6}+21x^{4}-14x^{3}):7/2x^{2}` `=-2x^{4}+6x^{2}-4x`
`4)``(15x^{3}y^{3}-10x^{2}y^{3}+25x^{2}y^{2}):(5x^{2}y^{2})` `=3xy-2y+5`
`5)``(-8x^{7}y^{2}+12x^{4}y-4x^{3}y):8x^{3}y` `=-x^{4}y+3/2x-1/2`
`6)``(-18x^{6}+9x^{4}-12x^{3}):9/4x^{2}` `=-8x^{4}+4x^{2}-16/3x`