1. on the mp had 11 straight line double-1 ko in parallel C/m: 2 straight line created with each 1 degree17 < corner
2. For (O) the diameter AB. C in addition to line segment AB (C lies on the straight line AB). 2 guystangential CE and CF AB cut EF at I, the cat onlineCMN. C/m: AIM angle = angle of BIN
3. For triangle ABC outreach circle (O). Know D, E, F isthe next point, D in AC, AB, F E in B.C. Know OE = r,AB = c, AC = b, BC = a
C/m: a) 1 (a + b + c) * r = 2S (S is the area of triangle ABC)
b) if (a + b + c) (a + b-c) = 4S, the triangle ABC square
