Based on the brevity of the original post, if one is to assume that both System 9.2 and MacOS X (unknown version) are installed, then use the 'System Preferences' 'Startup Disk' utility - to locate, select, and boot MacOS X from.
Otherwise, a properly detailed post may be necessary.
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Added 29 Dec. 2005, at 09.07.
Opps, by 'System Preferences' 'Startup Disk' utility - I meant select the 'Apple, Control Panels, Startup Disk' sub-menu item.
I actually did perform the above 'Apple ... Startup Disk' sub-menu item process within System 9.2.2, and then (for some unknown reason) wrote the reply via a MacOS X point of view.
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