`-10y^2 xx (2xy)^3 xx (-x)^2`

`= -10y^2 xx 8x^3y^3 xx x^2`

`= ( -10 xx 8 ) xx (x^3 xx x^2) xx (y^2 xx y^3)`

`= -80 xx x^(3+2) xx y^(2+3)`

`= -80x^5y^5`

`= -80(xy)^5`