Answer:
13
Step-by-step explanation:
To find AB, we need to find BD.
Do this by using Pythagorean’s theorem
Square root of 20 squared minus 16 squared =Square root of 400-256 = Square root of 144 = 12cm
Use Pythagorus Theorem to find the measure of AB
AB = √DA^2 + BD^2
AB = √25 + 144
AB = √169 = 13
Hope this helps
