Quadratic Equation

Just came across with a program for quadratic equations. I am not sure where the code is coming from but it certainly works. It will ask you the values A, B and C from the formula Ax^2+Bx+C=0


Blue key, R/S [PRGM]

Line   Instruction          Description, input.  
______________________________________________________________
  Q001   LBL Q         , program's name "Q"
  Q002   CF 10         , Yellow key, up arrow [FLAGS], 2CF, 10        
  Q003   INPUT A      
  Q004   INPUT B      
  Q005   INPUT C      
  Q006   -B÷(2xA)     
  Q007   ENTER        
  Q008   ENTER        
  Q009   B^2-4xAxC    
  Q010   x>=0?        
  Q011   GTO Q017     
  Q012   +/-          
  Q013   sqrt         ;press k key
  Q014   i            
  Q015   x            
  Q016   GTO Q018     
  Q017   sqrt         
  Q018   2xA          
  Q019   ÷            
  Q020   +            
  Q021   x<>y         
  Q022   LASTx        
  Q023   -            
  Q024   RTN          

Execute the program: XEQ Q ENTER. Enter A, B and C according to the equation Ax^2+Bx+C=0. It will show both solutions in x and y registers.