Advanced Geometry Section 3.8 The HL Postulate Learner Objective: Students will solve proofs and problems using the HL Postulate of triangle congruence.
Warm Up Statement Reason
How can we prove that triangles are congruent?
What about SSA? In these triangles, two pairs of corresponding sides and a NON-INCLUDED pair of corresponding angles are congruent. Do the triangles appear to be congruent?
There is one special case when SSA does prove triangles are congruent There is one special case when SSA does prove triangles are congruent. This occurs when the corresponding angles are RIGHT ANGLES which makes the congruent sides a HYPOTENUSE and a LEG of the RIGHT triangle.
H-L Postulate If there exists a correspondence between the vertices of two RIGHT TRIANGLES such that the Hypotenuse and a Leg of one triangle are congruent to the corresponding parts of the other triangle, then the two RIGHT TRIANGLES are congruent. ONLY APPLIES TO RIGHT TRIANGLES!
STATEMENTS REASONS Given: Prove: bisects A C B D
Prove: Corresponding angle bisectors of congruent triangles are congruent. STATEMENTS REASONS D E F H A B C G Given: Prove: bisects
HW: Pg. 158 # 1,2,6,7,10,12,15