Respuesta :
Answer:
AC = 12
Step-by-step explanation:
If BC is parallel to DE, then angles D and B are congruent and angles C and E are congruent as well. This means that triangles ABC and ADE are similar by the AAA (or AA) similarity theorem.
We know that similar triangles are in proportion. This means that [tex]\frac{AC}{AE} = \frac{AB}{AD}[/tex]
Now, we can plug the values given into that equation:
[tex]\frac{x}{x+15} = \frac{8}{18}[/tex]
Now, cross multiply:
18x = 8(x + 15)
Now, we can simplify this equation and solve for x, or AC.
18x = 8x + 120
Subtract 8x from both sides:
10x = 120
Divide both sides by 10:
x = 12
Hope this helps!