find each side length. Round to the nearest tenth if necessary

x = 8.5
The other two sides are given in the diagram.
The Pythagorean theorem tells you ...
... 19² = 17² +x²
Subtracting 17², we have ...
... x² = 361 -289 = 72
Taking the square root gives x.
... x = √72 = 6√2
... x ≈ 8.5