Geometry Lesson 4 – 8 Triangles and Coordinate Proof Objective: Position and label triangles for use in coordinate proofs. Write coordinate proofs.

Slides:



Advertisements
Similar presentations
11/10/14 Geometry Bellwork. Formulas to Remember.
Advertisements

Placing Figures on Coordinate Plane
Lesson 4-7 Triangles and Coordinate Proof
Warm Up Evaluate. 1. Find the midpoint between (0, 2x) and (2y, 2z).
Coordinate Geometry Mrs. Keating Keystone Geometry.
Proving the Midsegment of a Triangle Adapted from Walch Education.
4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Section 8.3 Connections Between Algebra & Geometry
You have used coordinate geometry to find the midpoint of a line segment and to find the distance between two points. Coordinate geometry can also be used.
Introduction to Coordinate Proof
4.7 Triangles and Coordinate Proof
Warm Up Complete each statement.
Splash Screen. Lesson Menu Five-Minute Check (over Lesson 4–7) CCSS Then/Now New Vocabulary Example 1:Position and Label a Triangle Key Concept: Placing.
Attention Teachers: The main focus of section 7 should be proving that the four coordinates of a quadrilateral form a _______. 9th and 10th graders should.
4-8 Introduction to Coordinate Proof
Isosceles Triangles & Coordinate Proof
Isosceles and equilateral triangles
4-9 Isosceles and Equilateral Triangles
Splash Screen. Lesson Menu Five-Minute Check (over Lesson 4–7) NGSSS Then/Now New Vocabulary Example 1: Position and Label a Triangle Key Concept: Placing.
Warm Up Lesson Presentation Lesson Quiz Holt Geometry.
4-7 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
5.7: Proofs Using Coordinate Geometry Expectations: G1.1.5: Given a line segment in terms of its endpoints in the coordinate plane, determine its length.
Triangles and Lines – Introduction to Triangles
5.1 – Midsegment Theorem and Coordinate Proof
Warm-up Write the following formulas 1.Distance 2.Midpoint What is the Pythagorean Theorem?
Section 5.1 Midsegment Theorem and Coordinate Proof.
5.1.1 Midsegment Theorem and Coordinate Proof SWBAT: Define and use mid-segment of a triangle and mid-segment theorem to solve problems. You will accomplish.
Unit 5 Review State Standards 2: Write geometric proofs. 5: Prove triangles are congruent. 12: Find and use measures of sides and angles in triangles.
Introduction to Coordinate Proof
Triangles and Coordinate Proof
Chapter 4 Midterm Review By MD Squared (Matthew Tsai/Fu and David Ellis/Sang)
4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Rectangular Coordinates Objectives: Use the Distance Formula Use the Midpoint Formula.
Transparency 2 Review: Lesson 4-6 Mini-Quiz. Class Greeting.
Lesson 7 Menu 1.Name two congruent segments if  1   2 2.Name two congruent angles if RS  RT. 3.Find m  R if m  RUV = Find m  C if ΔABC is.
Lesson 7 Menu 1.In the figure, ABCD is an isosceles trapezoid with median EF. Find m  D if m  A = Find x if AD = 3x 2 – 5 and BC = x Find.
Splash Screen.
4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Warm Up Problem of the Day Lesson Presentation Lesson Quizzes.
Splash Screen.
Introduction to Coordinate Proof
Triangles and Coordinate Proof
Triangles and Coordinate Proof
4.8 Triangles and Coordinate Proofs
4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Introduction to Coordinate Proof
Unit 5 Lesson 4.7 Triangles and Coordinate Proofs
Splash Screen.
Introduction to Coordinate Proof
4.9: Isosceles & equilateral triangles
4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Introduction to Coordinate Proof
Five-Minute Check (over Lesson 4-6) Main Ideas and Vocabulary
4-9 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Introduction to Coordinate Proof
Section 4.8 Notes: Triangles and Coordinate Proof
4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Introduction to Coordinate Proof
Bell Ringer What does the isosceles triangle theorem prove?
4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Isosceles and Equilateral Triangles
Rectangular Coordinates
4-8 Isosceles and Equilateral Triangles Warm Up Lesson Presentation
Five-Minute Check (over Lesson 4–6) Mathematical Practices Then/Now
GEOMETRY Section 4.7 Intro to Coordinate Proofs
4.8 Notes: Coordinate Proofs
BELLWORK Find the midpoint between the following pairs of points.
Presentation transcript:

Geometry Lesson 4 – 8 Triangles and Coordinate Proof Objective: Position and label triangles for use in coordinate proofs. Write coordinate proofs.

Coordinate Proof Coordinate proof – use figures in the coordinate plane and algebra to prove geometric concepts.

Key Concept 1. Use the origin as a vertex or center of the triangle. 2. Place at least one side of a triangle on an axis. 3. Keep the triangle within the first quadrant if possible. 4. Use coordinates that make computations as simple as possible.

Position and label right triangle MNP on the coordinate plane so that leg MN is a units long and leg NP is b units long.

Position and label isosceles triangle JKL on the coordinate plane so that its base JL is a units long, vertex K is on the y-axis, and the height of the triangle is b units.

Identify Missing Coordinates of isosceles triangle XYZ Z (a, 0) X (0, 0)

Name the missing coordinates of isosceles right triangle ABC. B (0, 0) C (a, 0) A (0, a)

Write a coordinate proof to show that a line segment joining the midpoints of two sides of a triangle is parallel to the third side. Sketch a picture. Use numbers that will make the problem easier. Midpoint deals with dividing by 2 so use multiples of 2 to make it simple. Cont…

Proof Using Midpoint formula: Using Slope formula: Since the slopes are equal,

The Bermuda Triangle is a region formed by Miami, Florida, San Jose, Puerto Rico, and Bermuda. The approximate coordinates are given. Write a coordinate proof to prove the Bermuda triangle is scalene. Since all sides are different, Triangle MBP is scalene.

Homework Pg – 4 all, 8 – 18 E, 32, 38 – 46 E