Geometry: Partial Proofs with Congruent Triangles.

Slides:



Advertisements
Similar presentations
How do we prove triangles congruent using Side-Side-Side Postulate?
Advertisements

Sec 2-6 Concept: Proving statements about segments and angles Objective: Given a statement, prove it as measured by a s.g.
GEOMETRY Proving Triangles are Congruent: ASA and AAS.
3-1: Congruent Figures Honors Geometry.
Congruent Triangles – Pairs of Triangles Page 11.
Chapter 4 Congruent Triangles.
Module 5 Lesson 2 – Part 2 Writing Proofs
What are the ways we can prove triangles congruent? A B C D Angle C is congruent to angle A Angle ADB is congruent to angle CDB BD is congruent to BD A.
Writing Triangle Proofs
Similar Triangle Proofs Page 5-7. A CB HF E Similar Triangle Proof Notes To prove two triangles are similar, you only need to prove that 2 corresponding.
TODAY IN GEOMETRY…  Learning Target: PROOF-A-RAMA Work in groups to prove triangles are congruent  Independent practice.
TODAY IN GEOMETRY… REVIEW: Solutions for PROOF-A-RAMA 2
Honors Geometry Intro. to Geometric Proofs. Before we can consider geometric proofs, we need to review important definitions and postulates from Unit.
Geometry Section 3.3 part 2: Partial Proofs Involving Parallel Lines
GEOMETRY 3.4 Perpendicular Lines. LEARNING TARGETS  Students should be able to…  Prove and apply theorems about perpendicular lines.
Lesson 2.6 p. 109 Proving Statements about Angles Goal: to begin two-column proofs about congruent angles.
Jan. 12 th Use your addition skills to fill in missing numbers so all columns, rows, and diagonals add up to the number in the squares along the right.
Prove Theorems Advanced Geometry Deductive Reasoning Lesson 4.
Proving Triangles Congruent STUDENTS WILL BE ABLE TO… PROVE TRIANGLES CONGRUENT WITH A TWO COLUMN PROOF USE CPCTC TO DRAW CONCLUSIONS ABOUT CONGRUENT TRIANGLES.
Proof Quiz Review 13 Questions…Pay Attention. A postulate is this.
Angles and Parallel Lines
3.3 – Proves Lines are Parallel
Warm-Up x + 2 3x - 6 What is the value of x?. Geometry 3-3 Proving Lines Parallel.
Triangle Congruency - CPCTC Mixed Problems. Corresponding Parts of Congruent Triangles are Congruent This rule is used AFTER we have proven two triangles.
Unit 2 Part 4 Proving Triangles Congruent. Angle – Side – Angle Postulate If two angles and the included side of a triangle are congruent to two angles.
Mini Vocabulary Proofs Unit 6 – Day 2. Vertical Angles – Never-Given-Given #1 1 2 StatementReason1) Mark the picture!!! Q.E.D.
POINTS, LINES AND PLANES Learning Target 5D I can read and write two column proofs involving Triangle Congruence. Geometry 5-3, 5-5 & 5-6 Proving Triangles.
Proving Lines Parallel
Topic 1 Summary Segments and Angles. Segment Addition Postulate Example 1Example 2.
Isosceles Triangle Theorem (Base Angles Theorem)
Δ CAT is congruent to Δ DOG. Write the three congruence statements for their SIDES
The answers to the review are below. Alternate Exterior Angles Postulate Linear Pair Theorem BiconditionalConclusion Corresponding Angles Postulate 4 Supplementary.
DefinitionsTrue / False Postulates and Theorems Lines and Angles Proof.
Perpendicular and Angle Bisectors Perpendicular Bisector – A line, segment, or ray that passes through the midpoint of a side of a triangle and is perpendicular.
Chapter 4 Review Cut-n-Paste Proofs. StatementsReasons SAS Postulate X is midpoint of AC Definition of Midpoint Given Vertical Angles Theorem X is midpoint.
Using Special Quadrilaterals
StatementsReasons 1. ________________________________ 2.  1   2 3. ________________________________ 4. ________________________________ 1. ______________________________.
Transversal t intersects lines s and c. A transversal is a line that intersects two coplanar lines at two distinct points.
4-4 Using Corresponding Parts of Congruent Triangles I can determine whether corresponding parts of triangles are congruent. I can write a two column proof.
Chapters 2 – 4 Proofs practice. Chapter 2 Proofs Practice Commonly used properties, definitions, and postulates  Transitive property  Substitution property.
Do Now.
Geometry Notes Sections .
Using Triangle Congruence to Prove Sides and Angles Congruent C h. 5-2
Aim: How do we prove triangles congruent using the Angle-Angle-Side Theorem? Do Now: In each case, which postulate can be used to prove the triangles congruent?
Corresponding Angles Postulate
Do Now Find the value of x that will make a parallel to b. (7x – 8)°
Isosceles and Equilateral Triangles Ch. 5-3
Warm Up (on the ChromeBook cart)
Warm-Up Determine if the following triangles are congruent and name the postulate/definitions/properties/theorems that would be used to prove them congruent.
3-2 Angles & Parallel Lines
Proof and Perpendicular Lines
Two-Column Triangle Proofs
Ways to Prove Triangles Congruent
Warm Up (on handout).
Aim: Do Now: ( ) A B C D E Ans: S.A.S. Postulate Ans: Ans:
Mathematical Justifications
Proving Lines Parallel
Warm Up Take out your placemat and discuss it with your neighbor.
What theorems apply to isosceles and equilateral triangles?
5.3 Congruent Triangles & Proof
Properties of parallel Lines
Ex: Given: Prove: CPCTC:
Converse Definition The statement obtained by reversing the hypothesis and conclusion of a conditional.
I .Complete the Following Proof (6 steps, Statement 4 has two parts)
2-6 Prove Statements About Segments and Angles
4.4 Prove Triangles Congruent by SAS and HL
Unit 2: Congruence, Similarity, & Proofs
2.7 Prove Theorems about Lines and Angles
3-2 Proving Lines Parallel
Parallel Lines and Transversals
Presentation transcript:

Geometry: Partial Proofs with Congruent Triangles

Recall, that we do proofs in two columns. In the left-hand column we In the right-hand column we

Further recall, that the reason for the first statement is always ______ while the reason for each succeeding statement must be a _________, _________ or ________.

These are the definitions, postulates and theorems that we will use as reasons in our proofs.

DEFINITIONS: If two lines are perpendicular, then A midpoint of a segment is

DEFINITIONS: An angle bisector is Vertical angles are

DEFINITIONS: Alternate interior angles are Corresponding angles are

POSTULATES: Corresponding Angles Postulate: If two angles are corresponding angles, then Reflexive Postulate:

THEOREMS: Vertical Angle Theorem: If two angles are vertical angles, then Alternate Interior Angle Theorem: If two angles are alternate interior angles, then Right Angle Theorem: If two angles are right angles then,

In addition to the above definitions, postulates and theorems, you will use the four congruent shortcuts, _____, _____, _____, and _____, as your reason for why two triangles are congruent.

Examples: Complete each proof by supplying the missing statements and reasons.