Question

Calcule x, sabendo que BC//EF

Answer 1

Pode ser usado o Teorema de Tales:

$\frac{10}{x} = \frac{4}{6} \\\\ 4x = 60 \\\\ \boxed{\boxed{x = 15}}$

Answer 2

Teorema de Tales:

4           6
---  =  ------
10         x

4x = 10.6
4x = 60
x = 60/4
x = 15