Question

5p 2. Inălţimea unui triunghi echilateral este 43 cm. Aria triunghiului este:
a) 64 cm;
b) 1673 cm;
c) 873 cm;
d) 48 cm
Repede pls!!​

Answer 1

Răspuns:

Sper ca înțelegi din poză

Answer 2

$\it h=\dfrac{\ell \sqrt3}{2} \Rightarrow 43=\dfrac{\ell\sqrt3}{2}|_{\cdot2} \Rightarrow 86=\ell\sqrt3 \Rightarrow \ell=\dfrac{^{\sqrt3)}86}{\ \ \sqrt3}=\dfrac{86\sqrt3}{3}\\ \\ \\ \mathcal{A}=\dfrac{1}{2}\cdot \ell \cdot h=\dfrac{1}{2}\cdot\dfrac{86\sqrt3}{3}\cdot43=\dfrac{43\sqrt3}{3}\cdot43=\dfrac{1849\sqrt3}{3}\ cm^2$