X550¶
MIDPOINT OF X3 AND X20
X550 (MIDPOINT OF X3 AND X20) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶
Constructed Elements
Central Lines: {3, 20} (Euler line)
Related Centers: X3 (CIRCUMCENTER), X20 (DE LONGCHAMPS POINT)
Alternate Coordinates5 forms
Trilinears: \(2 \sec A - 3 \sec B \sec C : 2 \sec B - 3 \sec C \sec A : 2 \sec C - 3 \sec A \sec B\)
Trilinears: \(6 \cos A + \cos B \cos C - 3 \sin B \sin C : :\)
Trilinears: \(\cos A - 4 \cos B \cos C + 2 \sin B \sin C : :\)
Trilinears: \(6 \cos B \cos C - 2 \sin B \sin C - \cos(B - C) : :\)
Trilinears: \(5 \cos A + \cos(B - C) - \cos B \cos C - 3 \sin B \sin C : :\)
Incident Central Lines9 lines
Functional Relations17 relations
X550 = reflection of Xi in Xj for these (i,j): (3, 548), (4, 140), (5, 3), (382, 546)
X550 = isogonal conjugate of X16835
X550 = complement of X382
X550 = anticomplement of X546
X550 = intersection of tangents to Evans conic at X17 and X18
X550 = radical center of reflections of nine-point circle in A, B, C
X550 = radical trace of circumcircle and Trinh circle
Notes¶
As a point on the Euler line, X550 has Shinagawa coefficients \((3,-5)\).
Let OA be the circle centered at the A-vertex of the anticomplementary triangle and passing through A; define OB and OC cyclically. X550 is the radical center of OA, OB, OC. (Randy Hutson, August 30, 2020)
Let OA be the circle centered at the A-vertex of the anti-Euler triangle and passing through A; define OB and OC cyclically. X550 is the radical center of OA, OB, OC. (Randy Hutson, August 30, 2020)