The length of BC = 72
Solution:
Given ΔABC and ΔDEF are similar triangles.
ΔABC ΔDEF
AB = 54, BC = n, EF = 12, DE = 9
Similar triangle theorem:
If two triangles are similar then the corresponding sides are proportional to each other.
Substitute the given values, we get
Do cross multiplication.
Divide both sides of the equation by 9.
⇒ BC = 72
Option B is the correct answer.
The length of BC = 72.