Question

Aflati EF daca Bl=3cm

Answer 1

BI||EF=> (TFA) IAB~FAE=>

$\frac{ai}{iv} = \frac{ab}{be} = \frac{bi}{ef}$

$\frac{ai}{iv} = \frac{ib}{ef}$

Notam cu x=AI

$\frac{x}{4x} = \frac{3}{ef}$

$\frac{1}{4} = \frac{3}{ef}$

=> EF=12 cm