Lesson 3: Parallel Lines and the Triangle Angle-Sum Theorem

Slides:

Advertisements

Similar presentations

3.5 Parallel Lines and Triangles

Advertisements

Parallel Lines and the Triangle Angle-Sum Theorem

DO NOW 1) X = 180 2) 55 + X = 180 3) X + 58 = 90 4) 31 + X = 90.

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.

Blue – 2/23/2015 Gold – 2/24/ Name 2 pair of alternate interior angles  5 &  3 and  4 &  1 2. What is the sum of m  1 + m  2 + m  3? 180°

Applying Triangle Sum Properties

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

Triangles 1 The Basics. 2 Naming Triangles For example, we can call the following triangle: Triangles are named by using its vertices. ∆ABC∆BAC ∆CAB∆CBA∆BCA.

Lesson 3: (3.4) Parallel Lines and the Triangle Angle-Sum Theorem

Classify Triangles Standard 4C.

Chapter 4 Congruent Triangles. 4.1 & 4.6 Triangles and Angles Triangle: a figure formed by three segments joining three noncollinear points. Classification.

3.4 & 4.5 Triangles.

2.7 – Triangles. Type of ∆DefinitionPicture Equilateral Triangle CLASSIFICATION BY SIDES All sides are ≅

Classifying Triangles Angle Measures of Triangles.

Triangles 11.2.

Warmup – grab a book Room , submit answers for x and y.

Triangles Part 1 The sum of the angles in a triangle is always equal to: 180°

Triangle Fundamentals

Triangles: Angle Sum & Classifying Triangles Tutorial 12b.

3-3 Parallel Lines & the Triangle Angle Sum Theorem M11.B B Objectives: 1) To classify triangles and find the measures of their angles. 2) To.

Section 3-4: Parallel Lines and the Triangle Angle-Sum Theorem.

Objectives: Classify triangles and find the measures of their angles Use the exterior angles of triangles.

4.1 & 4.2 A Notes. Type of ∆DefinitionPicture Equilateral Triangle CLASSIFICATION BY SIDES All sides are 

Triangles Geometry Mr. Zampetti Unit 3, Day 1. Today’s Objectives To learn new strategies that will help find the measures of angles in a triangle To.

Triangle A polygon with three sides and three angles. A triangle can be names by its’ side lengths and angles. – Side lengths: isosceles, equilateral,

Triangle Classification. Objectives Classify triangles by their angle and side measures Find the sum of the measure of the interior and exterior angles.

Classify triangles by sides No congruent sides Scalene triangle At least two sides congruent Isosceles triangle Three congruent sides Equilateral triangle.

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

4-1 Triangles and Angles. Theorem 4.1: Triangle Sum The sum of the measures of the interior angles of a triangle is 180 . xx yy zz  x +

Triangle Angle Sum Theorem, Triangle Exterior Angle Theorem

Lesson: Objectives: 4.1 Classifying Triangles  To IDENTIFY parts of triangles  To CLASSIFY Triangles by their Parts.

Section 3-3 Parallel Lines and the Triangle Angle-Sum Theorem.

3-4 Parallel Lines and the Triangle Angle-Sum Theorem Objectives: 1) to classify triangles and find the measures of their angles 2) To use exterior angles.

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

Scalene triangle: A scalene triangle is a triangle that has no equal sides. The following is a scalene triangle.

Warm Ups Classify each angle Classify each angle Solve Each Equation x= x+105= x + 58 = x = 90.

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

Triangles The sum of the measures of the angles of a triangle is 180 degrees. m A + m B + m C = 180 o A BC An angle formed by a side and an extension.

Triangles Chapter What is the sum of the angles inside a triangle? 180º? Prove it m Given A B C Angle Addition Postulate/Definition of a Straight.

3-4 Angles of a Triangle. A Triangle is a figure formed by three segments joining three noncollinear points. 1) Classifying triangles by their sides.

4-1 Classifying Triangles SWBAT: Identify and classify triangles by angle measures and side measures. G.6.

Classify These Triangles by Sides and Angles. Chapter 4 Congruent Triangles Section 4.1: Triangle Sum Properties Todays Objective: Determine if a right.

4.1 Triangle Angle Sum and Properties. How many degrees in a triangle? The sum of the angles in any triangle is exactly 180 degrees.

Applying Triangle Sum Properties

Warm Up 5-1 Classify each angle as acute, obtuse, or right

Triangle Angle Sum Theorem, Triangle Exterior Angle Theorem

Chapter 4: Congruent Triangles

Lesson 3: (3.4) Parallel Lines and the Triangle Angle-Sum Theorem

Geometry 4.1 Triangle and Angles.

Bellwork Classify each angle as acute, obtuse, or right. 90° 72° 116°

Angles of Triangles 4.2.

3-3 & 3-4 Parallel Lines & the Triangle Angle-Sum Theorem

Section 3-4 Angles of a Triangle.

Chapter 4: Congruent Triangles

Triangles Created by G. Antidormi 2005.

Objectives -triangle names -remote interior -exterior

4.1 Classifying Triangles

Unit 4 – Lesson 1 Apply Triangle Sum Properties

Objective - To classify triangles.

Triangles Guided Notes

Bellringer 3. slope 1/3 , y-intercept  (2, 3), (1, 6)

Triangle Fundamentals

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.

Chapter 4: Triangles Classifying Triangles by sides:

3-3 Parallel Lines & the Triangle Angle Sum Theorem

4.1 – Apply triangle sum properties

Brett Solberg – AHS – ’11-’12

Module 15: Lesson 1 Interior & Exterior Angles

Presentation transcript:

Lesson 3: Parallel Lines and the Triangle Angle-Sum Theorem SWBAT: Classify triangles and find the measures of their angles. Use exterior angles of triangles.

What are we learning? Students will be able to: Classify triangles and find the measures of their angles. Use exterior angles of triangles to solve problems.

Finding Angle Measures in Triangles C 50° 35° A B Theorem 3-12: Triangle Angle-Sum Theorem: The sum of the measures of the angles of a triangle is 180.

Finding Angle Measures in Triangles C 50° 35° A B Find the measure of the three angles. Justify your work.

Finding Angle Measures in Triangles Find the values of x, y, and z. Justify your work. 39° 21° 65° x° y° z° F J H

Finding Angle Measures in Triangles B Find the values of x, y, and z. x° y° 62° z° 49° A C D

Classifications of Triangles Equiangular Acute Right Obtuse Equilateral Isosceles Scalene

Classifications of Triangles Classify the following triangles by their angles and sides. 3 in. 4 in. 5 in. 7 cm. 16 cm. 106° 37° Draw an equilateral right triangle. NOT POSSIBLE!!!

Using Exterior Angles of Triangles Exterior Angle of a Polygon: An angle formed by a side and an extension of an adjacent side. Remote Interior Angles Exterior Angle 1 2 3 Remote Interior Angles: The two nonadjacent interior angles corresponding to each exterior angle of a triangle.

Using Exterior Angles of Triangles 1 2 3 Theorem 3-13: Triangle Exterior Angle Theorem: The measure of each exterior angle of a triangle equals the sum of the measures of its two remote interior angles.

Using Exterior Angles of Triangles 100° x° 50° Find the measure of the x. Justify your work.

Using Exterior Angles of Triangles Find the values of w, x, y, and z. 97° x° y° 53° w° 86° z°

Little More Practice Find the value of x. (80 – 2x)° (70 – 3x)°