1. Isosceles Triangles Theorems Theorem 8.12 – If two sides of a triangle are equal in measure, then the angles opposite those sides are equal in measure. CONVERSE CONVERSE Theorem 8.13 – If two angles of a triangle are equal in measure, then the sides opposite those angles are equal in measure.

2. Equilateral Triangles Theorems Theorem 8.14 – If a triangle is equilateral, then it is also equiangular, with three 60 angles. CONVERSE CONVERSE Theorem 8.15 – If a triangle is equiangular, then it is also equilateral.

3. Perpendicular Bisector Theorem Theorem 8.16 – If a point is the same distance from both endpoints of a segment, then it lies on the perpendicular bisector of the segment