Answer:
DE = 6
Explanation:
Let's consider some theorem:
1- The line joining the midpoints of two sides of a triangle is parallel to the third side and equal to equal to half of it
2. A straight line through the mid point of one side of a triangle parallel to a second side bisects the third side.
Having noted that, let's see that;
∆ ABC is similar to ∆ BAC
Therefore, from the above theorem and the information given,
(DE / AC) = ( BE / BC)
From the question, BC is 10
Therefore,
(DE/12) = (5 / 10)
Cross multiplying:
10*DE = 12*5
10DE = 60
DE = 60/10
DE = 6
Hope that helped.