Question

bună seara! ma poate ajuta cineva la aceasta problema?​

Answer 1

Răspuns:

Ai răspuns atașat pe foaie.

Answer 2

Notăm: AB=2a, BC=2b, FD=FC=a,  ED=EA=b

$\it \mathcal{A}_{ABCD} = AB\cdot BC=2a\cdot 2b=4ab\\ \\ \mathcal{A}_{BEF}=\mathcal{A}_{ABCD}-(\mathcal{A}_{D EF}+\mathcal{A}_{CFD}+\mathcal{A}_{ABE})=4ab-\dfrac{ab+2ab+2ab}{2}=\\ \\ \\ =4ab-\dfrac{5ab}{2}=ab(4-2,5)=1,5ab\\ \\ \\ \dfrac{\mathcal{A}_{BEF}}{\mathcal{A}_{ABCD}}=\dfrac{1,5ab}{4ab}=\dfrac{^{2)}1,5}{\ 4}=\dfrac{3}{8}\\ \\ \\ R\breve aspunsul\ \ corect\ \ este\ \ c)\ \dfrac{3}{8}$