Answer:
13 is the answer
Step-by-step explanation:
YZ is 4+√55 cm.
[tex]a^2+b^2=c^2[/tex]
[tex]3^2+b^2=5^2[/tex]
[tex]9+b^2=25[/tex]
[tex]b^2=16\\b=4[/tex]
[tex]a^2+b^2=c^2\\3^2+b^2=8^2\\9+b^2=64\\b^2=55\\b=\sqrt{55}[/tex]
4+√55