△ XYZ∼ △ DEF, YZ is 10 meters, XZ is 15 meters, and EF is 8 meters. What is DF?
Solution:
As, △ XYZ∼ △ DEF , so the ratio of sides of triangle is equal.
So, we have, 
Using, 
So, we get,
Now, to solve for DF, we must simplify
Simplifying,

To simplify, Let us multiply by 4*DF on both sides


So, 5 DF=15*4=60
To solve for DF, let us divide by 5 on both sides


So, DF=12meters