Zadanie 101

Dane: $AB = 4$, $AC = 10$, $BD = 3$.
$$\frac{3}{DC} = \frac{4}{10} = \frac{2}{5}.$$ $$\frac{3}{DC} = \frac{2}{5} \Rightarrow 3 \cdot 5 = 2 \cdot DC \Rightarrow 15 = 2DC \Rightarrow DC = 7{,}5.$$ $$BC = BD + DC = 3 + 7{,}5 = 10{,}5.$$ Odpowiedź: $DC = 7{,}5$, $BC = 10{,}5$.