The possible numbers that fills the blanks are
GH = 10, BH = 7
LK = 15, HK = 7
How to fill the blanks
The blanks are filled using the concept of similar triangles. Since
In this case, the constant of proportionality used is constant, such that
DB / AB = DH / GH = DK / LK
5 / 7 = 10 / (7 + 7) = 15 / (7 + 7 + 7) = 0.71429
5 / 7 = 10 / (14) = 15 / (21) = 0.71429
OR
5/15 = 7/21 = 1/3
OR
10/15 = 14/21 = 2/3
Proportions taken from the similar triangles will be equal.