Respuesta :

gmany

Answer:

B. 28

Step-by-step explanation:

If ΔABC ~ ΔDEC, then the corresponding sides are in proportion:

[tex]\dfrac{AC}{DC}=\dfrac{AB}{DE}[/tex]

We have:

[tex]AC=x\\DC=32-x\\AB=42\\DE=6[/tex]

Substitute:

[tex]\dfrac{x}{32-x}=\dfrac{42}{6}[/tex]

[tex]\dfrac{x}{32-x}=\dfrac{7}{1}[/tex]                cross multiply

[tex](1)(x)=(32-x)(7)[/tex]            use distributive property

[tex]x=(32)(7)+(-x)(7)[/tex]

[tex]x=224-7x[/tex]           add 7x to both sides

[tex]8x=224[/tex]             divide both sides by 8

[tex]x=28[/tex]