Isosceles Triangles. Sec: 4.6 Sol: G.5. 3. Leg. Leg. 1. 2. Base. Properties of Isosceles Triangles. An isosceles triangle is a triangle with two congruent sides. The congruent sides are called legs and the third side is called the base. Vertex. Base Angles. A. B. C.
An isosceles triangle is a triangle with two congruent sides.
The congruent sides are called legs and the third side is called the base.
If two sides of a triangle are congruent, then the angles opposite those sides (base angles) are congruent.
What is the measure of
3x - 7
If two angles of a triangle are congruent, then the sides opposite those angles are congruent.
Find the value of x.
Since two angles are congruent, the
sides opposite these angles must be
3x – 7 = x + 15
2x = 22
X = 11
Lesson 3-2: Isosceles Triangle
4.3 A triangle is equilateral if and only if it is equiangular.
4.4 Each angle of an equilateral triangle measures 60°.
Find the measure of angle 1 and 2:
Solve for X:
Classwork: WB pg 51 1-6
Homework: Worksheet 4-6