Answer:
12.5 units
Step-by-step explanation:
We are given that:
ΔABC ~ ΔDEC
This means that the similarity proportion can be set up as follows:
AB/DE = BC/EC / AC/DC
We have:
CD = 5 units
BC = 6 + 4 = 10 units
EC = 4 units
This means that:
BC/EC = AC/DC
10/4 = AC / 5
Therefore,
AC = (5*10) / (4) = 12.5 units
Hope this helps :)