Answer:
B
Step-by-step explanation:
The 2 triangles are similar, so the corresponding sides are in proportion, that is
[tex]\frac{DE}{XY}[/tex] = [tex]\frac{FD}{ZX}[/tex] , substitute values
[tex]\frac{DE}{9}[/tex] = [tex]\frac{8}{12}[/tex] ( cross- multiply )
12 DE = 72 ( divide both sides by 12 )
DE = 6 → B
