HP 48G - Manual (Page 62)

S t e p 4 - Define a new variable, T H , from this equation. &)
stores the expression to the right of the equal sign
(' Q.--''U.---'H+TL ') in the variable name to the left of the equal
sign. Press
(VAR
I afterwards to view the new entry in the
menu.
S)
(VAR)
5-8 Solving Equations