MARKING AS BRAINLIEST (Geometry)

Answer:
x = 9.43
Step-by-step explanation:
As you can see by the right angle symbol, this is a right-angled triangle meaning to find x we can simply use Pythagoras theorem:
[tex]a^2 + b^2 = c^2[/tex]
Simply plug the given sides into this equation:
[tex]8^2 + 5^2 = x^2[/tex]
64 + 25 = 89
[tex]89 = x^2[/tex]
Now square root both sides to find x:
[tex]\sqrt{x^2} = \sqrt{89}[/tex]
x = 9.43
Hope this helps!