Answer:
The unknown side is 15 in.
Step-by-step explanation:
[tex]a^2+b^2=c^2[/tex]
[tex]a^2+8^2=17^2[/tex]
[tex]a^2+64=289[/tex]
[tex]a^2=289-64[/tex]
[tex]a^2=225[/tex]
[tex]a=15[/tex]