抛物线y=﹣

1

5

x²+

2

5

x﹣1，经过配方化成y=a（x﹣h）²+k的形式是（   ）

A：$y=\frac{1}{5}{\left(x+1\right)}^2-\frac{4}{5}$

B：$y=-\frac{1}{5}{\left(x-1\right)}^2+\frac{4}{5}$

C：y=﹣ $\frac{1}{5}$ （x﹣1）²﹣ $\frac{4}{5}$ ．

D：$y=\frac{1}{5}{\left(x+1\right)}^2+\frac{4}{5}$