Interactive Applet |
You can move the points A, B and C (click on the point and drag it).
Press the keys “+” and “−” to zoom in or zoom out the visualization window and use the arrow keys to translate it.
You can also construct all centers related with this one (as described in ETC) using the “Run Macro Tool”. To do this, click on the icon , select the center name from the list and, then, click on the vertices A, B and C successively.
Information from Kimberling's Encyclopedia of Triangle Centers |
Trilinears (b + c - a)/a : (c + a - b)/b : (a + b - c)/c
= csc2(A/2) : csc2(B/2) : csc2(C/2)Barycentrics b + c - a : c + a - b : a + b - c
Let A'B'C' be the points in which the A-excircle meets BC, the B-excircle meets CA, and the C-excircle meets AB, respectively. The lines AA', BB', CC' concur in X(8). Another construction of A' is to start at A and trace around ABC half its perimeter, and similarly for B' and C'. Also, X(8) is the incenter of the anticomplementary triangle.
X(8) lies on these lines:
1,2 3,100 4,72 5,1389 6,594 7,65 9,346 11,1320 19,1891 20,40 21,55 29,219 31,987 33,1039 34,1041 35,993 37,941 38,986 56,404 57,1219 58,996 76,668 79,758 80,149 81,1010 101,1311 140,1483 144,516 171,1468 175,1270 176,1271 177,556 178,236 181,959 190,528 192,256 193,894 194,730 197,1603 210,312 213,981 220,294 221,651 224,914 238,983 253,307 274,1002 277,1280 278,1257 291,330 314,1264 315,760 326,1442 344,480 348,664 392,1000 405,943 406,1061 442,495 443,942 474,999 475,1063 491,1267 595,1724 599,1086 631,1385 643,1098 726,1278 860,1068 908,946 961,1460 1015,1574 1016,1083 1034,1895 1036,1183 1124,1377 1211,1834 1281,1282 1317,1388 1335,1378 1500,1573 1672,1680 1673,1681 1674,1679 1675,1679 1857,1896X(8) is the {X(69),X(75)}-harmonic conjugate of X(7).
X(8) = reflection of X(I) in X(J) for these (I,J): (1,10), (4,355), (20,40), (100,1145), (145,1), (149,80), (192,984), (390,9), (944,2), (962,4), (1320,11), (1482,5), (1483,140)
X(8) = isogonal conjugate of X(56)
X(8) = isotomic conjugate of X(7)
X(8) = cyclocevian conjugate of X(189)
X(8) = complement of X(145)
X(8) = anticomplement of X(1)
X(8) = anticomplementary conjugate of X(8)
X(8) = X(I)-Ceva conjugate of X(J) for these (I,J): (69,329), (72,2), (312,346), (314,312), (333,9)X(8) = X(I)-cross conjugate of X(J) for these (I,J):
(1,280), (9,2), (10,318), (11,522), (55,281), (72,78), (200,346), (210,9), (219,345), (497,7), (521,100)X(8) = cevapoint of X(I) and X(J) for these (I,J):
(1,40), (2,144), (6,197), (9,200), (10,72), (11,522), (55,219), (175,176)X(8) = crosspoint of X(I) and X(J) for these (I,J): (75,312), (314,333)
X(8) = crosssum of X(I) and X(J) for these (I,J):
(1,978), (31,604), (57,1423), (667,1015), (1042,1410), (1400,1402)X(8) = crossdifference of any two points on line X(649)X(854)
X(8) = X(1)-aleph conjugate of X(1050)
X(8) = X(I)-beth conjugate of X(J) for these (I,J): (8,1), (341,341), (643,3), (668,8), (1043,8)