Answer: 5 sqrt (2)
Explanation:
ABCD is a square
BCD is a triangle
BC=DC=5
To find DB
Let BC= a, DC=b, BD=c.
using Pythagoras Theorem in Triangle BCD
c2 = a2+b2
c2 = 52+52
c2= 25+25
c= √(50)
c2= √(25)×√ (2)
c= √(5× 5) √(2)
c= 5√(2) or c=5sqrt(2)
Rmbr, Let BC= a, DC=b, BD=c.