What is ST 2x - 2 RT 64?

The expression "ST 2x - 2 RT 64" appears to be a combination of variables and constants, but it is not formatted as a standard mathematical expression. If "ST" and "RT" represent functions or operations, additional context is needed for clarification. However, if interpreted as "2x - 2√64," it simplifies to "2x - 16," since √64 equals 8. Please provide more context for a more accurate interpretation.