Look at the picture.
Use the Pythagorean theorem.
[tex](19+r)^2=r^2+35^2\\\\19^2+2\cdot19\cdot r+r^2=r^2+1225\ \ \ |-r^2\\\\361+38r=1225\ \ \ |-361\\\\38r=864\ \ \ |:38\\\\r\approx22.737[/tex]
The diameter d = 2r.
Therefore
[tex]d=2\cdot22.737=45.474\approx45.5[/tex]
Answer: 45.5
