HP 35s Scientific Calculator - Manual (Page 321)

ALG: Summary C-13
Linear Regression
Linear regression, or L.R. (also called linear estimation), is a statistical method for
finding a straight line that best fits a set of x,y–data.
To find an estimated value for x (or y), key in a given hypothetical value for y
(or x) ,press  , then press   ( ) (or  Õ ( )).
To find the values that define the line that best fits your data, press  
followed by (), (), or ().
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