Answer:
x = 9
Step-by-step explanation:
The parallel lines divide the sides of the triangle in proportion, that is
[tex]\frac{20-8}{x}[/tex] = [tex]\frac{8}{6}[/tex]
[tex]\frac{12}{x}[/tex] = [tex]\frac{8}{6}[/tex] ( cross- multiply )
8x = 72 ( divide both sides by 8 )
x = 9
