How to detect a location is in or not in a selected area ?

[TubaKumbara]

Hello.

In silverlight

I have 2 variables (example)

Latd = 25.334
Longtd = 23.765


I will draw a circle on my map ( I can doing it already, no problem) and i will press a button

And i want to show a messagebox such as

("The Location is in your selected area")

Or

("The Location is not in your selected area")

so, how can i detect my Location ( Latd = 25.334, Longtd = 23.765) in or not in selected circular area.

[TubaKumbara]

Im waiting an answer. can someone help me please.

I want to detect, Is specific location in selected area or not.

[TubaKumbara]

ok i found solution

http://resources.esri.com/help/9.3/arcgisserver/apis/silverlight/samples/start.htm#Relation