Isosceles Triangles, Equilateral Triangles, HL Theorem, CPCTC

Label all the parts of this isosceles triangle: vertex angle base angle base angle leg leg base What is special about an isosceles triangle? The base anglesin an isosceles triangle are congruentThe legs of an isosceles triangle are congruent. What is special about an equilateral triangle? The angles in an equilateral triangle are congruent.This means that the angles in an equilateral triangle must all be 60 degrees. We call these equiangular.The sides in an equilateral triangle are congruent. The following triangle is an equilateral triangle. One of the sides is 18 cm long. Fill in the missing information. 60 60 60 18 cm 18 cm 18 cm True or False: An Equilateral Triangle is a type of Isosceles Triangle True Identify the MOST SPECIFIC name; whether this is an Equilateral Triangle or an Isosceles Triangle Equilateral Triangle Isosceles Triangle The measure of angle HIG is equal to 40 degrees The Hypotenuse-Leg Theorem states: any two right triangles that have a congruent hypotenuse and a corresponding, congruent leg are congruent triangles What side is the hypotenuse of a right triangle? The side that is across from the right angle.The longest side of the right triangle. Using the Hypotenuse Leg Theorem, label the following triangles. Hypotenuse Hypotenuse Leg Leg Right Angle Right Angle A B C D F G H I What does CPCTC stand for? Corresponding Parts of Congruent Triangles are Congruent Instead of proving the triangles are congruent, take it a step further and prove: Angle LKW is congruent to Angle WAL Statements Reasons Angle KWL is congruent to Angle ALW Given Angle AWL is congruent to Angle WLK Given Side WL is congruent to side WL Reflexive Property of Congruence Triangle KWL is congruent to Triangle ALW ASA Angle LKW is congruent to Angle WAL CPCTC Form a two-column proof Statements Reasons Side PT is perpendicular to side AE Given Side AT is congruent to side TE Given Angle APT and Angle EPT are right angles Definition of Perpendicular Triangle APT and Triangle EPT are right triangles Definition of Right Triangles Side TP is congruent to side TP Reflexive Property of Congruence Triangle PAT is congruent to Triangle PET Hypotenuse Leg Theorem