Question

1. Determinati perimetrul unui triunghi echilateral cu aria de 25√3 cm².

Answer 1

$P=3*l \\ A= \frac{ \sqrt{3} }{4} * l^{2} \\ \frac{ \sqrt{3} }{4} l^{2} =25 \sqrt{3} \\ l^{2} =25 \sqrt{3} * \frac{4}{ \sqrt{3} } \\ l^{2} =100\\l=10cm\\P=3*10=30cm$