17. What is Angle AOB in degrees? In Euclidean geometry, any three points, when non-collinear, determine a unique triangle and simultaneously, a unique plane (i.e. Isosceles triangle. IF AB = AC, the triangle is isosceles. Split in half the triangle is a right triangle, so it's three angles are 90%, 55% and 70%. Explanation: J BCD is equilateral, so CBD is 60°. ( Prove that AD hisects &RAC. In the diagram below, ^ABC is shown with AC extended through point D. If mOBCD = 6x+ 2, mOBAC = 3x+ 15, and mOABC = 2x 1, what is the value of x? 6 In isosceles triangle ABC, AB =BC. What is the length of line segment AC? 46.5 C. 56 D. 83 8. Find the measure of