Hi!
To find this math problem your going to need to use a^2 + b^2 = c^2 (^2 means squared)
So if we look at the shape , they entire shape makes for triangles . (I'm going to be using the upper right triangle to solve this problem just so your following me)
So one side of the "triangle" is 6 and that's like the bottom of the triangle . And your hypotenuse is 10.
So using that formula , plug in 6 and 10 so we can find the other missing side
a^2 + 6^2 = 10^2
A^2 + 36 = 100
100-36 = 64
SQAURE ROOT of 64 = 8
Your missing side length is 8
8 + 8 = 16
DB= 16. ( you have to add them together to get the full length)
I hope this helps you :)