Final answer:
To find the length of EC, we can use the concept of similar triangles. Setting up a proportion, we find that EC is equal to 7.5.
Step-by-step explanation:
To find the length of EC, we can use the concept of similar triangles. Since EC is parallel to AB, we can see that triangle AEC and triangle ABC are similar. This means that their corresponding sides are proportional. We can set up the following proportion:
AE/AB = EC/BC
Substituting the given values, we have:
10/20 = EC/15
Cross multiplying, we get:
EC = (10/20) * 15 = 7.5
Therefore, the length of EC is 7.5.