4.8: Isosceles & Equilateral Triangles Objective: To understand and apply properties of isosceles and equilateral triangles. Supplies: Math Notebook Assignment:

Slides:

Advertisements

Similar presentations

4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

Advertisements

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

4-8 Isosceles and Equilateral Triangles Lesson Presentation

4.6 Isosceles Triangles.

8.Bottom left corner at (0,0), rest of coordinates at (2, 0), (0, 2) and (2, 2) 9. Coordinates at (0,0), (0, 1), (5, 0) or (0,0), (1, 0), (0, 5) 10. Using.

Isosceles and Equilateral Triangles Chapter 4 Section 5.

ISOSCELES TRIANGLES 1 Modified by Lisa Palen. PARTS OF AN ISOSCELES TRIANGLE An isosceles triangle is a triangle with at least two congruent sides. The.

Objectives Prove theorems about isosceles and equilateral triangles.

Holt McDougal Geometry 4-8 Isosceles and Equilateral Triangles Prove theorems about isosceles and equilateral triangles. Apply properties of isosceles.

4.5 Isosceles and Equilateral Triangles. Isosceles Triangles At least two sides are of equal length. It also has two congruent angles. Base Angles Base.

Isosceles and Equilateral Triangles Section 5-1. Isosceles Triangle A triangle with at least two congruent sides. Leg Leg Base Vertex Angle Base Angles.

Warm-Up Find the value of x. x x - 3. GEOMETRY 4-8 Isosceles and Equilateral Triangles.

1 4-5 Isosceles and Equilateral Triangles State and apply the Isosceles Triangle Theorem and its converse State and apply the corollaries for equilateral.

Use Isosceles and Equilateral Triangles

Quiz Tell whether the pair of triangles is congruent or not and why

Isosceles and equilateral triangles

4-6 Isosceles & Equilateral Triangles

CH. 4.7 USE ISOSCELES & EQUILATERAL TRIANGLES. VOCAB Leg: 2 sides of isosceles triangle Leg Vertex Angle: Angle formed by the two legs Base: 3 rd side.

Geometry Ms. Stawicki.  1) To use and apply properties of isosceles triangles.

4.7 Use Isosceles & Equilateral Triangles

Section 4-4: The Isosceles Triangle Theorems

Section 4-5: Isosceles and Equilateral Triangles.

4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4-7 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4.6: Isosceles and Equilateral Triangles

4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

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

4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

Warm Up 1. Find each angle measure. True or False. If false explain.

Holt Geometry 4-8 Isosceles and Equilateral Triangles 4-8 Isosceles and Equilateral Triangles Holt Geometry Warm Up Warm Up Lesson Presentation Lesson.

4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4-5 Isosceles and Equilateral Triangles

5.4 Isosceles and Equilateral Triangles

Objectives Prove theorems about isosceles and equilateral triangles.

4.7 Use Isosceles and Equilateral Triangles

4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

Geometry 4.1 Triangle and Angles.

Isosceles & Equilateral Triangles

Types of Triangles and Their Properties

Section 4.5 isosceles & equilateral triangles

4.9: Isosceles & equilateral triangles

4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

Objective: To use and apply properties of isosceles triangles.

Lesson 3-2 Isosceles Triangles.

4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4.5 - Isosceles and Equilateral Triangles

4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

Isosceles, Equilateral, and Right Triangles

4-8 Isosceles and Equilateral Triangles Lesson Presentation

Objectives Prove theorems about isosceles and equilateral triangles.

4.6 Isosceles Triangles.

Isosceles and Equilateral Triangles

Isosceles and Equilateral Triangles

4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

Isosceles, Equilateral, and Right Triangles

Isosceles and Equilateral Triangles

(The Isosceles Triangle Theorems)

Warm Up 1. Find each angle measure. True or False. If false explain.

4.8 – Use Isosceles and Equilateral Triangles

4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation

Equilateral TRIANGLES

Isosceles and Equilateral Triangles

Quiz Friday Triangle Properties.

Objectives Prove theorems about isosceles and equilateral triangles.

Presentation transcript:

4.8: Isosceles & Equilateral Triangles Objective: To understand and apply properties of isosceles and equilateral triangles. Supplies: Math Notebook Assignment: 4.8 p. 276: 1-10, 12-16, 22-26

4.8: Isosceles & Equilateral Triangles VocabularySketchThings to Remember Isosceles Triangle 1.Legs 2.Vertex Angle 3.Base 4.Base Angles At least 2 legs are congruent. If 3 legs are congruent it is a special isosceles triangle called an equilateral triangle.

4.8: Isosceles & Equilateral Triangles Geometry Handbook p. 16 Note: The Isosceles Triangle Theorem is sometimes stated: Base angles of an isosceles triangle are congruent.

4.8: Isosceles & Equilateral Triangles If XY = 20 feet, explain why YZ is the same. Example 1: StatementJustification m∠X=40°Given m∠XZY+140°=180°Def of linear pair m∠XZY=180°-140°Subtraction property of equality m∠XZY=40°simplification m∠XZY= m∠XSubstitution property ∆XYZ is an isoscelesisosceles ∆ converse XY=YZdef of isosceles ∆ YZ=20 ftsubstitution.

4.8: Isosceles & Equilateral Triangles Find m  F. StatementJustification ED=EFGiven m∠E=22°given ∆DEF is an isosceles isosceles ∆ theorem ∠D≅∠F def of isosceles ∆ m ∠E+m∠F +m∠D=180° triangle sum theorem 22° +2m∠F =180° Substitution 2m∠F =158° subtraction POE m∠F =79° division POE.

4.8: Isosceles & Equilateral Triangles Find m  G. X+44=3x 44=2x 22=x m  G=22+44 m  G=66

4.8: Isosceles & Equilateral Triangles Converse of Equilateral  Corollary : If a triangle is equiangular, then it is equilateral. Equilateral  Corollary: If a triangle is equilateral, then it is equiangular.

4.8: Isosceles & Equilateral Triangles Find the value of x. 2x+32=60 2x=28 X=14

4.8: Isosceles & Equilateral Triangles Find the value of y. 5y-6=4y+12 Y=18

4.8: Isosceles & Equilateral Triangles Assignment: 4.8 p. 276: 1-10, 12-16, Next week final on Thursday 1/22 Final will be about 50 multiple choice questions covering all material from the beginning of the school year. After the final if you choose you can retake up to 5 ~10 point quizzes or tests. Please look at your progress report to decide which, if any quizzes or tests you would like to retake. Write which tests or quizzes you want to retake on your progress report and turn in by end of class Friday, so I can print out those quizzes or tests out.