Question

daca AC=20 cm, iar B e (AC), folosind proportii derivate, determina a) AB, stiind ca AB/BC = 2/3 b) BC, stiind ca AB/AC=3/10

dau coroanaaa help meh

Answer 1

a)daca$\frac{AB}{BC}$=$\frac{2}{3}$ adunand numaratorul la numitor rezulta

$\frac{AB}{AB+BC}$=$\frac{2}{2+3}$⇒

⇒$\frac{AB}{AC}$=$\frac{2}{5}$⇒

⇒AB=$\frac{AC*2}{5}$=$\frac{40}{5}$=8

b)daca$\frac{AB}{AC}$=$\frac{3}{10}$ ⇒AB=$\frac{AC*3}{10}$=$\frac{60}{10}$=6

AC=AB+BC ⇒BC=AC-AB=20-6=14