Explicație pas cu pas:
ΔABC dreptunghic, ∢A = 90°,
AB = 9 cm, AC = 12 cm, BC = 15 cm
[tex]Aria_{(ABC)} = \frac{AB \times AC}{2} = \frac{9 \times 12}{2} = 54 \: {cm}^{2} \\ [/tex]
[tex]\sin(C) = \frac{AB}{BC} = \frac{9}{15} = \frac{3}{5} \\ = > \sin(C) = \frac{3}{5} [/tex]
[tex]\tan(B) = \frac{AC}{AB} = \frac{12}{9} = \frac{4}{3} \\ = > \tan(B) = \frac{4}{3} [/tex]
