\(=\dfrac{4\left(x-2\right)}{x+5}\cdot\dfrac{\left(x+5\right)\left(x-5\right)}{x\left(x-2\right)}=\dfrac{4x-20}{x}\)
\(\dfrac{4x-8}{x+5}.\dfrac{25-x^2}{2x-x^2}=\dfrac{4\left(x-2\right)}{x+5}.\dfrac{\left(x+5\right)\left(x-5\right)}{x\left(x-2\right)}=\dfrac{4\left(x-5\right)}{x}\)