Assume each square is 1 unit.
The base of the large triangle is 6 units and the base of the smaller triangle is 3 units.
The scale factor is 1/2
I don’t not know the answer for this question sorry
Let us draw a picture to make the things more clear.
Attached is the image.
We have been given that

Therefore, we have

Now, in triangle bcd, we have

Now, in triangle acb, we have

Thus, ad is 15 cm.
100000000 needed to take up space to give you answr