X140¶
MIDPOINT OF X3 AND X5
X140 (MIDPOINT OF X3 AND X5) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶
Constructed Elements
Central Lines: {3, 5} (Euler line)
Related Centers: X3 (CIRCUMCENTER), X5 (NINE-POINT CENTER)
Alternate Coordinates7 forms
Trilinears: \(\cos A + 2 \sin B \sin C : \cos B + 2 \sin C \sin A : \cos C + 2 \sin A \sin B\)
Trilinears: \(3 \cos A + 2 \cos B \cos C : 3 \cos B + 2 \cos C \cos A : 3 \cos C + 2 \cos A \cos B\)
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: \(bc[b \cos(C - A) + c \cos(B - A)] : :\)
Barycentrics: \(3 - \cot B \cot C : :\)
Barycentrics: \(2a^{4} - 3a^{2}(b^{2} + c^{2}) + (b^{2} - c^{2})^{2} : :\)
Barycentrics: \(3 S^{2} - S_{B} S_{C} : :\)
Linear Combinations1 combination
Incident Central Lines399 lines
{1, 5432}, {2, 3}, {6, 5418}, {8, 1483}, {9, 5843}, {10, 214}, {11, 35}, {12, 36}, {13, 5237}, {14, 5238}, {15, 18}, {16, 17}, {32, 3815}, {39, 230}, {40, 3624}, {46, 11375}, {49, 5012}, {51, 10263}, {52, 3917}, {53, 10979}, {54, 252}, {55, 496}, {56, 495}, {57, 6147}, {61, 395}, {62, 396}, {69, 1353}, {72, 10202}, {76, 6390}, {79, 5131}, {83, 2080}, {95, 340}, {98, 7832}, {100, 1484}, {104, 5260}, {110, 10264}, {113, 10990}, {114, 6292}, {115, 10992}, {119, 5251}, {125, 128}, {141, 182}, {142, 5762}, {143, 511}, {156, 9306}, {165, 8227}, {183, 3933}, {184, 13336}, {185, 5876}, {187, 1506}, {195, 323}, {216, 1990}, {231, 570}, {233, 6748}, {236, 8129}, {262, 7846}, {298, 628}, {299, 627}, {302, 633}, {303, 634}, {325, 1078}, {343, 569}, {355, 1698}, {371, 615}, {372, 590}, {385, 13571}, {389, 1154}, {392, 11729}, {394, 12161}, {484, 5443}, {485, 1152}, {486, 1151}, {497, 10386}, {515, 3634}, {516, 9955}, {517, 1125}, {518, 13373}, {523, 1116}, {524, 575}, {539, 11264}, {542, 6698}, {551, 10222}, {567, 3580}, {568, 7998}, {572, 1213}, {574, 3054}, {576, 597}, {577, 6749}, {578, 13567}, {601, 748}, {602, 750}, {618, 630}, {619, 629}, {620, 2782}, {623, 13350}, {624, 13349}, {625, 7830}, {626, 13335}, {671, 10185}, {758, 5885}, {908, 3916}, {912, 5044}, {930, 1263}, {936, 5791}, {942, 3911}, {944, 5790}, {946, 3579}, {956, 5552}, {958, 3820}, {970, 6703}, {971, 6666}, {993, 1329}, {999, 3085}, {1001, 10200}, {1007, 3785}, {1040, 8144}, {1056, 5265}, {1058, 5281}, {1071, 12691}, {1141, 11016}, {1145, 4861}, {1155, 12047}, {1173, 12834}, {1210, 12433}, {1319, 10039}, {1351, 3618}, {1352, 3763}, {1376, 10267}, {1387, 3057}, {1388, 12647}, {1478, 5204}, {1479, 5217}, {1482, 3616}, {1493, 13366}, {1503, 5092}, {1587, 6398}, {1588, 6221}, {1621, 11849}, {1697, 11373}, {1737, 2646}, {1768, 3652}, {1834, 4256}, {1837, 3612}, {1853, 9833}, {2077, 5259}, {2095, 5761}, {2548, 3053}, {2777, 5893}, {2794, 6721}, {2800, 13145}, {2808, 6710}, {2818, 6711}, {2831, 11259}, {2883, 3357}, {2888, 7666}, {2896, 7925}, {2979, 3567}, {3019, 13329}, {3068, 3312}, {3069, 3311}, {3070, 6396}, {3071, 6200}, {3086, 3295}, {3095, 7786}, {3096, 7940}, {3098, 5480}, {3167, 11411}, {3216, 5396}, {3303, 10072}, {3304, 10056}, {3316, 3590}, {3317, 3591}, {3336, 3649}, {3337, 5557}, {3419, 4855}, {3487, 5435}, {3488, 5704}, {3532, 4846}, {3581, 5888}, {3582, 3746}, {3583, 7173}, {3584, 5298}, {3585, 3614}, {3600, 8164}, {3601, 5722}, {3617, 7967}, {3619, 6776}, {3620, 11898}, {3622, 10247}, {3626, 13607}, {3630, 7916}, {3631, 5965}, {3653, 3679}, {3654, 7982}, {3655, 5881}, {3656, 7991}, {3678, 12005}, {3740, 12675}, {3767, 5013}, {3793, 7762}, {3813, 8715}, {3814, 5267}, {3816, 5248}, {3822, 5841}, {3824, 12436}, {3825, 5840}, {3826, 6796}, {3841, 5842}, {3898, 10284}, {3925, 10902}, {3927, 5744}, {4045, 7886}, {4255, 5292}, {4292, 5122}, {4293, 9654}, {4294, 9669}, {4297, 10175}, {4299, 10895}, {4302, 10896}, {4309, 11238}, {4317, 11237}, {4413, 11499}, {4423, 10310}, {5007, 9300}, {5010, 6284}, {5023, 7737}, {5024, 5286}, {5045, 13405}, {5080, 5303}, {5086, 10609}, {5097, 6329}, {5119, 11376}, {5126, 10106}, {5157, 13562}, {5171, 7808}, {5188, 7889}, {5206, 5475}, {5306, 7772}, {5309, 9607}, {5318, 10646}, {5321, 10645}, {5339, 11480}, {5340, 11481}, {5398, 5718}, {5403, 8160}, {5404, 8161}, {5414, 9661}, {5437, 5709}, {5438, 5705}, {5440, 6734}, {5446, 5943}, {5449, 12038}, {5486, 8548}, {5489, 5664}, {5534, 8580}, {5550, 5603}, {5562, 5650}, {5569, 7775}, {5587, 7987}, {5590, 5874}, {5591, 5875}, {5609, 5642}, {5640, 11465}, {5646, 5654}, {5651, 10539}, {5656, 13093}, {5658, 12684}, {5663, 5907}, {5687, 10527}, {5694, 5884}, {5720, 8726}, {5731, 5818}, {5743, 13323}, {5777, 11227}, {5878, 10606}, {5883, 11281}, {5889, 7999}, {5890, 11444}, {5894, 11204}, {5944, 12134}, {6000, 6696}, {6033, 7944}, {6055, 9167}, {6130, 8552}, {6153, 13433}, {6194, 7875}, {6199, 7582}, {6247, 6759}, {6248, 7820}, {6287, 9751}, {6321, 7847}, {6368, 10213}, {6395, 7581}, {6409, 6561}, {6410, 6560}, {6417, 7586}, {6418, 7585}, {6425, 9680}, {6449, 6459}, {6450, 6460}, {6455, 9541}, {6502, 9646}, {6592, 8902}, {6669, 6673}, {6670, 6674}, {6688, 10110}, {6722, 7861}, {6723, 11801}, {6746, 12363}, {7028, 8130}, {7280, 7354}, {7308, 7330}, {7603, 7747}, {7610, 12040}, {7616, 8859}, {7622, 7781}, {7697, 7835}, {7709, 7891}, {7735, 9605}, {7743, 10624}, {7750, 7752}, {7751, 13468}, {7756, 8589}, {7758, 8667}, {7761, 7862}, {7778, 7800}, {7801, 11168}, {7806, 12251}, {7810, 7821}, {7811, 7814}, {7831, 7899}, {7834, 9737}, {7844, 9734}, {7854, 7888}, {7863, 9466}, {7868, 9744}, {7881, 9755}, {7904, 7912}, {7914, 9996}, {7956, 8167}, {8071, 10320}, {8125, 8128}, {8126, 8127}, {8141, 10319}, {8148, 10595}, {8151, 10190}, {8666, 12607}, {8721, 9756}, {8722, 10358}, {9301, 10357}, {9655, 10590}, {9668, 10591}, {9704, 11003}, {9707, 11457}, {9729, 9820}, {9781, 11451}, {9826, 13416}, {10006, 11247}, {10163, 12506}, {10171, 12512}, {10189, 10280}, {10198, 11249}, {10225, 11813}, {10277, 13582}, {10517, 11916}, {10518, 11917}, {10541, 11179}, {10572, 12019}, {10574, 11459}, {10584, 11928}, {10585, 11929}, {10586, 12000}, {10587, 12001}, {10628, 11561}, {10915, 11260}, {10950, 11545}, {11015, 12690}, {11017, 13474}, {11176, 11615}, {11219, 12738}, {11246, 11544}, {11255, 11511}, {11265, 11513}, {11266, 11514}, {11267, 11515}, {11268, 11516}, {11426, 11433}, {11427, 11432}, {11430, 12241}, {11438, 12233}, {11485, 11489}, {11486, 11488}, {11703, 11792}, {11808, 13365}, {12162, 13491}, {12325, 13432}, {12358, 13148}, {13142, 13352}, {13470, 13565}
Functional Relations34 relations
X140 = midpoint of Xi and Xj for these (i,j): (3, 5), (141, 182), (389, 1216), (2883, 3357)
X140 = reflection of Xi in Xj for these (i,j): (546, 5), (547, 2), (548, 3)
X140 = isogonal conjugate of X1173
X140 = complement of X5
X140 = anticomplement of X3628
X140 = polar-circle-inverse of X37943
X140 = X2-Ceva conjugate of X233
X140 = crosspoint of Xi and Xj for these (i,j): (2, 95), (17, 18)
X140 = crosssum of Xi and Xj for these (i,j): (6, 51), (61, 62)
X140 = X5-of-medial triangle
X140 = center of circumconic that is locus of trilinear poles of lines passing through X233
X140 = intersection of tangents to Evans conic at X3070 and X3071
X140 = inverse-in-{circumcircle, nine-point circle}-inverter of X5189
X140 = center of inverse-in-{circumcircle, nine-point circle}-inverter of anticomplementary circle
X140 = centroid of the six circumcenters in the construction of the van Lamoen circle.
X140 = center of circle that is locus of crosssums of antipodes on the 2nd Lemoine circle
X140 = homothetic center of X4-altimedial and X140-anti-altimedial triangles
X140 = pole of van Aubel line wrt conic {X2,X15,X16,X17,X18}}
X140 = homothetic center of McCay and Moses-Steiner osculatory triangles
Notes¶
As a point on the Euler line, X140 has Shinagawa coefficients \((3, -1)\).
Let A' be the midpoint between A and X3, and define B' and C' cyclically; the triangle A'B'C' is homothetic to the medial triangle, and the center of homothety is X140. Let A″ be the centroid of the triangle BCX3, and define B″ and C″ cyclically; then A″B″C″ is homothetic to ABC, and the center of homothety is X140. Also, X140 is the center of the conic consisting of the centers of all the conics which pass through A, B, C, and X3. (Randy Hutson, 9/23/2011) This conic is also the locus of crosssums of the intersections of the circumcircle and lines through X4. Furthmore, this conic is the bicevian conic of X2 and X3. (Randy Hutson, 9/14/2016)
Let Oa be the circle centered at A and passing through the A-vertex of the Euler triangle; define Ob and Oc cyclically. The radical center of Oa, Ob, Oc is X140. (Randy Hutson, September 14, 2016)
Let Oa be the circle centered at A with radius 1/2*\(\sqrt{b^{2} + c^{2}}\), and define Ob and Oc cyclically. The radical center of Oa, Ob, Oc is X140. (Randy Hutson, September 14, 2016)
Let P be a point on the circumcircle. The bicevian conic of X2 and P is a rectangular hyperbola, H. Let X be the center of H. As P varies, X traces a circle centered at X140. (Randy Hutson, November 2, 2017)
X140 is the centroid of the six circumcenters in the construction of the van Lamoen circle. (Randy Hutson, October 15, 2018)