- 118 Views
- Uploaded on

Download Presentation
## PowerPoint Slideshow about ' Isosceles Triangles' - kenyon-valencia

**An Image/Link below is provided (as is) to download presentation**

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Leg

Leg

1

2

Base

Properties of Isosceles TrianglesAn 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

B

C

Theorem 4.9 Isosceles Triangle TheoremIf two sides of a triangle are congruent, then the angles opposite those sides (base angles) are congruent.

Given:Prove:

B

C

A

3x - 7

x+15

°

°

B

50

50

C

Theorem 4.10If two angles of a triangle are congruent, then the sides opposite those angles are congruent.

Example:

Find the value of x.

Since two angles are congruent, the

sides opposite these angles must be

congruent.

3x – 7 = x + 15

2x = 22

X = 11

Lesson 3-2: Isosceles Triangle

Example:

- Name Two Congruent Angles:
- Name Two Congruent Segments:

Properties of Equilateral Triangles

Corollaries:

4.3 A triangle is equilateral if and only if it is equiangular.

4.4 Each angle of an equilateral triangle measures 60°.

60°

60°

60°

Example: Triangle EFG is equilateral, and segment EH bisects angle E

Find the measure of angle 1 and 2:

Solve for X:

Download Presentation

Connecting to Server..