phi C=-l80-contrib phi C= 90 half phi c= phi c/2 half phi c 45 Because the line ba and od are parallel, the angle subtended by the line oab is also 135. thus angle OAB 135 angle BAD angle OAB/2 -half phi ci angle BEo angle OAB/2 half phi ci 2022-2-11 172022-2-11 17 phi_c = -180 - contrib phi_c = 90 half_phi_c = phi_c/2 half_phi_c = 45 Because the line BA and OD are parallel, the angle subtended by the line OAB is also 135°. Thus angle_OAB = 135; angle_BAD = angle_OAB/2 - half_phi_c; angle_BEO = angle_OAB/2 + half_phi_c;