SSS (Side-Side-Side)
AAS (Angle-Angle-Side)
(Rt. Tri. H-L) Right Triangle Hypotenuse Leg
CPCTC
Corresponding Parts of Congruent Triangles are Congruent
*can only use once you have proven triangles congruent*
Addition Postulate
If congruent pieces are added to congruent pieces, the whole piece is congruent.
Subtraction Postulate
If a congruent piece is subtracted from a whole congruent piece, the remaining piece is congruent.
Supplements of Congruent Angles are Congruent
Transitive
A = B
B = C Then we can say...
A = C
In a triangle if 2 sides are congruent, the opposite angles are congruent.
(you don't have to say its an isosceles triangle first)
In a triangle if 2 angles are congruent, the opposite sides are congruent.
(you don't have to say its an isosceles triangle first)
If you need to prove lines Parallel (ll)
if alternate-interior angles are congruent, then lines are parallel
OR
if corresponding angles are congruent, then lines are parallel
OR
if alternate-exterior angles are congruent, then lines are parallel
If using Right Triangle H-L to prove triangles congruent what MUST you include in your proof
You must name the triangles as being Right triangles
Once we proved triangles congruent what can we do?
Prove Corresponding parts congruent by Corresponding Parts of Congruent triangles are congruent (CPCTC)
