Divide: `5x^3-15 x^2+25x` by `5x`
`4z^3+6z^2-z` by `-1/2z`

Explanation

(i) `5x^3-15 x^2+25 x\ b y\ 5x`
`=(5x^3-15x^2+25x)/(5x)`
`=(5x^3)/(5x)-(15x^2)/(5x)+(25x)/(5x)`
`=x^2-3x+5`

(ii) `4z^3+6z^2-z\ b y-1/2z`
`=(4z^3+6z^2-z)/(-1/2z)`
`=(-2(4z^3+6z^2-z))/z`
`=(-8z^3)/z-(12z^2)/z+(2z)/z`
`=-8z^2-12z+2`