Answer:
8. Supplementary means that two angles add up to 180 degrees (straight line). For the justification, I would simply write "def. of supplementary angles."
9. Equilateral means that all sides equal. For the justification, I would simply write "def. of equilateral triangle."
10. In a circle, all radiuses equal in length. TC and ZC are both radiuses. For the justification, I would simply write "def. of radius."
11. A midpoint divides a line segment in half. For the justification, I would simply write "def. of midpoint."
