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What is 1 + 3?
Angle Sum Theorem
The angles in a triangle sum to 180
Third Angle Theorem
If 2 angles of 1 triangle are congruent to 2 angles of a second triangle then the third angles of the triangles are congruent
Exterior Angle Theorem
measure of the exterior angle is equal to the sum of the remote interior angles
corresponding parts of congruent triangles are congruent
if three sides of one triangle are congruent to three sides of a second, the triangles are congruent
if two angles and the included side of one triangle are congruent to two angles and the included side of the second, the triangles are congruent
if two angles and a non-included side of one triangle are congruent to the corresponding parts of another triangle, then the triangles are congruent
If two sides and the included angle of one triangle are equal to two sides and the included angle of another triangle, then the triangles are congruent
Isosceles Triangle Theorem
if 2 sides of a triangle are congruent, then the angles opposite those sides are congruent
Converse of the Isosceles Triangle Theorem
if 2 ∠s of a triangle are congruent, the opposite sides are congruent