Here's a sample of what you could do for your quadratic solver :

: ClrHome

: Prompt A

: Prompt B

: Prompt C

:(B^{2}-(4AC)) (STO->) X

:If X < 0

:DISP "NO REAL ANSWER"

: (-B+squareroot(X))/(2A) (STO->) Y

: (-B-squareroot(X))/(2A) (STO->) X

:

: Disp Y,X