Expression 22: "f" left parenthesis, "x" , right parenthesisfx
22
Expression 23: polygon left parenthesis, "A" , "B" , "P" , "C" , "P" , "B" , "C" , "D" , right parenthesispolygonA,B,P,C,P,B,C,D
23
Expression 24: "y" equals "f" prime left parenthesis, "P" Subscript, 1 , Baseline , right parenthesis left parenthesis, "x" minus "P" Subscript, 1 , Baseline , right parenthesis plus "f" left parenthesis, "P" Subscript, 1 , Baseline , right parenthesisy=f′P1x−P1+fP1