BF = X = 0.57735026919| Desmos

式19: "B" Subscript, 2 , Baseline equals StartRoot, 1 , EndRoot

式20: "C" Subscript, 2 , Baseline equals "A" Subscript, 2 , Baseline

式21: "m" Subscript, 1 , Baseline equals StartFraction, "B" Subscript, 2 , Baseline Over negative "C" Subscript, 1 , Baseline , EndFraction

式22: "y" equals "m" Subscript, 1 , Baseline left parenthesis, "x" minus "C" Subscript, 1 , Baseline , right parenthesis

式23: "y" equals StartFraction, negative 1 Over "m" Subscript, 1 , Baseline , EndFraction left parenthesis, "x" minus "A" Subscript, 1 , Baseline , right parenthesis

式24: "m" Subscript, 1 , Baseline left parenthesis, "x" minus "C" Subscript, 1 , Baseline , right parenthesis equals StartFraction, negative 1 Over "m" Subscript, 1 , Baseline , EndFraction left parenthesis, "x" minus "A" Subscript, 1 , Baseline , right parenthesis

式25: "D" Subscript, 1 , Baseline equals StartFraction, "m" Subscript, 1 , Baseline "C" Subscript, 1 , Baseline plus StartNestedFraction, 1 NestedOver "m" Subscript, 1 , Baseline , EndNestedFraction "A" Subscript, 1 , Baseline Over "m" Subscript, 1 , Baseline plus StartNestedFraction, 1 NestedOver "m" Subscript, 1 , Baseline , EndNestedFraction , EndFraction

式26: "D" Subscript, 2 , Baseline equals StartFraction, negative 1 Over "m" Subscript, 1 , Baseline , EndFraction left parenthesis, "D" Subscript, 1 , Baseline minus "A" Subscript, 1 , Baseline , right parenthesis

式27: "E" Subscript, 1 , Baseline equals "B" Subscript, 1 , Baseline plus 1 third left parenthesis, "C" Subscript, 1 , Baseline minus "B" Subscript, 1 , Baseline , right parenthesis

式28: "E" Subscript, 2 , Baseline equals "B" Subscript, 2 , Baseline plus 1 third left parenthesis, "C" Subscript, 2 , Baseline minus "B" Subscript, 2 , Baseline , right parenthesis

式29: "F" Subscript, 1 , Baseline equals "B" Subscript, 1 , Baseline plus "B" Subscript, "F" , Baseline cosine left parenthesis, "A" Subscript, "B" "C" , Baseline minus 90 minus "A" Subscript, "C" "B" , Baseline , right parenthesis

式30: "F" Subscript, 2 , Baseline equals "B" Subscript, 2 , Baseline plus "B" Subscript, "F" , Baseline sine left parenthesis, "A" Subscript, "B" "C" , Baseline minus 90 minus "A" Subscript, "C" "B" , Baseline , right parenthesis

Graphs

式32: left parenthesis, .1 , .1 minus .1 "t" , right parenthesis

式33: left parenthesis, .1 minus .1 "t" , .1 , right parenthesis

式34: polygon left parenthesis, "B" , "F" , right parenthesis

式35: polygon left parenthesis, "E" , "F" , right parenthesis

式36: polygon left parenthesis, "A" , "B" , "C" , right parenthesis

Points

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