Warm-up Find x a) b).

Slides:

Advertisements

Similar presentations

Warm Up Determine the measure of the missing interior angle. What type of triangle is it? Unit 8 - Lesson 2 Exterior Angles of a Triangle.

Advertisements

CH 4.7 USE ISOSCELES AND EQUILATERAL TRIANGLES. In this section… We will use the facts that we know about isosceles and equilateral triangles to solve.

The Triangle Sum Theorem.  The sum of the measures of the angles of a triangle are equal to 180 degrees < 5 = < 3 and < 4= < 1 because alternate.

3.5 Parallel Lines and Triangles

Unit 1 Angles formed by parallel lines. Standards MCC8G1-5.

4.2 Angles of Triangles Objectives: *Apply the Angle Sum Theorem.

An exterior angle is outside the triangle and next to one of the sides. 4-2 Exterior Angle Theorem.

3-5 Parallel Lines and Triangles

3-5 Parallel Lines and Triangles. Classification by Sides (NOT in the book!) Equilateral TriangleIsosceles Triangle Scalene Triangle 3 congruent sides2.

ANGLES OF TRIANGLES HEXAHEDRON: This is your standard cube, but "Hex" comes from the Greek meaning "six." About the only fascinating thing about this.

4-2 Angles of Triangles Objectives: The student will be able to: 1. Apply the Triangle-Sum Theorem. 2. Apply the Exterior Angle Theorem.

HOW TO FIND AN ANGLE MEASURE FOR A TRIANGLE WITH AN EXTENDED SIDE

Adapted from Walch Education Isosceles triangles have at least two congruent sides, called legs. The angle created by the intersection of the legs is.

Classifying Triangles Angle Measures of Triangles.

5-6 Inequalities in One Triangle

Triangles and Lines – Sum of the Angles in a Triangle The sum of the angles in any triangle = 180°

Types of Triangles And Angle Sum Theorems.  Notation for sides.  AB CB AC  Angles   ABC or  B  Vertex angle  Base angle  Opposite side  Opposite.

ANGLES OF A TRIANGLE Section 4.2. Angles of a Triangle Interior angles  Original three angles of a triangle Exterior angles  Angles that are adjacent.

Goal, to classify triangles by their sides and by their angles.

Triangle Angle Sum Theorem, Triangle Exterior Angle Theorem

Triangle Sum Theorem The sum of the angle measures in a triangle is 180 degrees.

I can use theorems, postulates and/or definitions to prove theorems about triangles including: measures of interior angles of a triangle sum to 180 degrees.

Geometry Triangles. Vocabulary  Theorem 4-1 (angle sum theorem): The sum of the measures of the angles of a triangle is 180 In order to prove the angle.

3.5 Parallel Lines and Triangles

Triangles and Angles Classifying Triangles. Triangle Classification by Sides Equilateral 3 congruent sides Isosceles 2 congruent sides Scalene No congruent.

Angles of Triangles Angle Sum Theorem The sum of the measures of the angles of a triangle is 180 degrees. Third Angle Theorem If two angles of one triangle.

Triangle Theorems. Warm-Ups 1.What do you think is going well with this class? 2.What is your favorite part of the class? 3.What do you wish was different.

Chapter 3 Lesson 3 Objective: To use exterior angles of triangles.

3.4.  The sum of the measures of the angles of a triangle is 180.

3-5 Parallel Lines and Triangles I can apply the triangle angle sum theorem to find the values of variables. I can apply the exterior angle theorem to.

Triangles and Their Angles Geometry – Section 4.1.

 Scalene Triangle No sides congruent  Isosceles Triangle Exactly 2 sides congruent  Equilateral Triangle All sides congruent.

CH. 4.1 APPLY TRIANGLE SUM PROPERTIES. VOCAB Interior Angles : angles inside the triangle (sum = 180) Exterior Angles: angles outside the triangle Interior.

Use isosceles and equilateral triangles

Use isosceles and equilateral triangles

Isosceles Triangles.

Triangle Angle Sum Theorem, Triangle Exterior Angle Theorem

Angles of Triangles.

Measuring Angles in Triangles

Chapter 4: Congruent Triangles

Name the type of triangle shown below.

Angle Theorems for Triangles

Geometry 4.1 Triangle and Angles.

3.5 Parallel lines and Triangles

11-4 Exterior Angles of Triangles

Angles of Triangles 4.2.

Exterior Angles of Triangles

Properties of Triangles

A C B Triangle Sum Theorem (4.1)

Types of Triangles and Their Properties

Exterior Angles of Triangles

Inside angles theorem.

Warm-up Find x a) b).

Warm-up Find x a) b).

L J M K (2x – 15)0 x0 500.

V L T The sum of the interior angles of a triangle is 180 degrees.

Parallel Lines, Transversals, Base Angles & Exterior Angles

Triangle Theorems.

Use isosceles and equilateral triangles

Base Angles & Exterior Angles

Drill 1) x = 180, solve for x 2) How many degrees do the interior angles of a triangle add up to. 3) What type of triangle has an angle that.

Exterior Angles in a Triangle

Isosceles Triangles. Isosceles Triangles Base Angles If 2 angles in a triangle are congruent, then the sides opposite them are congruent.

Converse Definition The statement obtained by reversing the hypothesis and conclusion of a conditional.

Isosceles Triangles. Isosceles Triangles Base Angles If 2 angles in a triangle are congruent, then the sides opposite them are congruent.

Exterior Angle Theorem

3-3 Parallel Lines & the Triangle Angle Sum Theorem

Vertical Angles, Linear Pairs, Exterior Angles

Module 15: Lesson 1 Interior & Exterior Angles

Presentation transcript:

Warm-up Find x a) b)

Base Angles & Exterior Angles

Base Angles If 2 angles in a triangle are congruent, then the sides opposite them are congruent.

Solve for x. 2x + 25 = 7 2x = -18 12 x = -9

Base Angles If 2 sides in a triangle are congruent, then the angles opposite them are congruent.

Solve for x. 6x + 1 = 55 6x = 54 3 x = 9

Exterior Angle Theorem The measure of an exterior angle of a triangle is equal to the sum of the measures of the two non-adjacent interior angles of the triangle.

Solve for x. 3x - 10 = x + 15 + 25 2x = 50 x = 25