Błagam pomóżciena teraz!! Nic z tego nie kumam. DAJE NAJJ

[latex]2left(dfrac{1}{2}-2dfrac{1}{4} ight)-0,8=\ 2left(dfrac{1}{2}-dfrac{9}{4} ight)-dfrac{8}{10}=\ 2left(dfrac{1}{2}-dfrac{9}{4} ight)-dfrac{8}{10}=\ 1-dfrac{9}{2}-dfrac{8}{10}=\ dfrac{10}{10}-dfrac{45}{10}-dfrac{8}{10}=\ -dfrac{43}{10}=-4,3[/latex]