Question

How do I find this ?

Answer 1

The radius
`\overline{SU}=\overline{ST}=\overline{SV}`

The diameter:
`\overline{TU}`

The chord
`\overline{WX}` and diameter is a chord.

`\overline{TU}=2\overline{SV}` therefore if
`|\overline{SV}|=9`

then
`|\overline{TU}|=2\cdot9=18`

Answer 2

notice if we know the side SV = 9, then... wait a second!!!! SV is the radius of the circle, but but but, TS is also a radius, but but but, SU is also a radius.

TU = TS + SU

TU = 9 + 9.

recall, the radius is the same length no matter how you slant it.