Question

qual e o perimetro de um triangulo equilatero cuja altura mede 18cm

Answer 1

Pela fórmula:
$h= \frac{l \sqrt{3} }{2}$

$18= \frac{l \sqrt{3} }{2}$

$l \sqrt{3} =36$

$l= \frac{36}{ \sqrt{3} }. \frac{ \sqrt{3} }{ \sqrt{3} }$

$l= \frac{36 \sqrt{3} }{3}$

$l=12 \sqrt{3}~cm$

$\boxed{P=3l}$
$P=3.12 \sqrt{3}$
$P=36 \sqrt{3}~cm$