3.6A Lines in the coordinate plane (Writing & classifying equations)

Slides:



Advertisements
Similar presentations
Parallel & Perpendicular Slopes II
Advertisements

2.4 Write Equations of Lines
Parallel and Perpendicular Lines
Objective - To write equations of parallel and perpendicular lines. Graph the following on the coordinate plane. x y Parallel lines have the same slope.
Unit 1 Basics of Geometry Linear Functions.
4.4 Parallel and Perpendicular Lines
Warm-Up On the same coordinate plane… ▫Graph the equation y=2x +3 ▫Graph the equation y=2x ▫Graph the equation y= - ½x + 1 What do you notice about the.
Writing an Equation Using Two Points Goal: to write an equation of a line, in slope intercept form, that passes through two points.
Perpendicular Lines Sec 3.7 Goals: To identify perpendicular lines using slope To write equations of perpendicular lines.
OBJECTIVES: STUDENTS WILL BE ABLE TO… IDENTIFY IF 2 LINES ARE PARALLEL, PERPENDICULAR OR NEITHER GRAPH A LINE PARALLEL OR PERPENDICULAR TO ANOTHER WRITE.
LINEAR SYSTEMS – Graphing Method In this module, we will be graphing two linear equations on one coordinate plane and seeing where they intersect. You.
Answers. Write the Formulas Slope Formula y₂-y₁ x₂-x₁ Point Slope Form y-y₁=m(x-x₁) Slope-intercept Form y=mx+b.
5.6 Parallel and Perpendicular Lines
Do Now Write the slope-intercept equation of this line.
2.4 Writing Equations of Lines. We’ve learned to graph given an equation. Now we’ll learn to write the equation given the graph There are three ways.
2.4 Writing Equations of Lines p. 91. Learning Target I can write equations of a line.
Lines in the Coordinate Plane
Warm-Up 5 minutes 1. Graph the line y = 3x + 4.
I can determine when lines are parallel and write equations of parallel lines.
Holt Geometry 3-6 Lines in the Coordinate Plane 3-6 Lines in the Coordinate Plane Holt Geometry Warm Up Warm Up Lesson Presentation Lesson Presentation.
Holt McDougal Geometry 3-6 Lines in the Coordinate Plane 3-6 Lines in the Coordinate Plane Holt Geometry Warm Up Warm Up Lesson Presentation Lesson Presentation.
3.6 and 3.7 slopes of ll and Lines. Standard/Objectives: Standard 3: Students will learn and apply geometric concepts. Objectives: Find slopes of lines.
Slope Intercept and Point Slope Formulas. Slope Intercept Formula Y = MX + b  M is the slope of the equation  X is the input of the equation  B is.
5-3A Vocabulary 5.) Linear equation 6.) y-intercept 7.) Slope-intercept form.
Slope Intercept form. Geometry Unit 2-3, 2-4 Equations of lines Parallel and perpendicular slopes.
Lines Slope measures the “steepness” of a line. Slope or
1.5 Writing Equations of Parallel and Perpendicular Lines
1-5 Writing Equations of Parallel and Perpendicular Lines
Writing Equations of Lines
Lesson 3-6 Part 2 Point-Slope Equation.
6.1 Solving Systems of Linear Equations by Graphing
Parallel and Perpendicular Lines
3-1 Graphing Systems of Equations
Parallel and Perpendicular Lines
2-4B Writing equations for Parallel & Perpendicular lines
Parallel and Perpendicular Lines
Linear Models and Rates of Change
Systems of Equations Solving by Graphing.
Parallel Lines: SLOPES ARE THE SAME!!
Writing Equations of Lines
Section 5 – Writing Equations of Parallel and Perpendicular Lines
Finding the equation of a line
3.1 Notes: Solving Systems of Equations
5-6 Parallel and Perpendicular Lines
Graph the equation..
X and Y Intercepts.
Systems of Equations Solving by Graphing.
2.5 Writing Equations in Slope Intercept Form
Warm-Up Solve the system by graphing..
6-1 Solving Systems by Graphing
Objectives Graph lines and write their equations in slope-intercept and point-slope form. Classify lines as parallel, intersecting, or coinciding.
Parallel and Perpendicular
3-5: Vocabulary rise, run, slope point-slope form of a line
3-5: Vocabulary rise, run, slope point-slope form of a line
2-3C Parallel and Perpendicular Lines
Remember, there are four types of slope:
Lines in the Coordinate Plane
SYSTEMS.
Slope-Point Form of the Equation for a Linear Function
Chapter 6 Vocabulary (6-1)
1.2 Solving Linear Systems by Graphing
2.4 Writing Equations of Lines
Chapter 9 Lesson 3 Pg. 699 Solving Systems of Equations by Graphing
PERPENDICULAR LINES.
Chapter 9 Lesson 3 Pg. 699 Solving Systems of Equations by Graphing
Chapter 3: Parallel & Perpendicular Lines
2.4A Writing Equations of Lines
Warm-Up 1.) Using the point slope formula find the equation of a line with slope -2 , passing through the point (1, 3) 2.) Graph the line y = 3x + 4.
Chapter 4 Review.
Presentation transcript:

3.6A Lines in the coordinate plane (Writing & classifying equations) Geometry

We’ve learned to graph given an equation. Now we’ll learn to write the equation given the graph There are three ways. It all depends on what information you are given as to which process you use.

A.)Given the slope, m, and the y-intercept, b, use the equation y=mx+b Ex. 1 The y-intercept is -3 b=-3 The slope is 4/3 The equation is: y = x – 3 3 4

B.) If you are given slope, m, and a point (x1,y1) on the line Use Point Slope Form: y – y1 = m ( x – x1)

Ex. 2 Write an equation of a line containing the point (1,2) with slope of -1/2. Use (x1,y1) = (1,2) & m = -1/2 y – 2 = -1/2 ( x – 1) Now you can simplify to the slope intercept form y – 2 = -1/2 x + ½ y = -1/2 x + 5/2

C.) Given two points Use slope formula first. Then, either use point-slope formula or slope-intercept form twice.

Ex. 3 Given two points (-2,2) & (3,7) Find the slope: m=1 Plug this slope and one of the points into the point slope formula. y – 2 = 1 ( x – (-2)) y – 2 = x + 2 y = x + 4 (put the equation into slope intercept form) (3,7) (-2,2)

Classification of lines Parallel lines have same slope with different y-intercept. Intersecting lines have different slopes. Coinciding lines have same slope & same y-intercept. (IMS)

Ex. 4 Determine whether the lines are parallel, intersect or coincide. 6x - 12y = -24, 3y = 2x + 18 intersect

3-6B Writing equations of lines parallel or perp. Lines & graphs

Write equations of parallel or perpendicular lines Ex. 1 Write an equation of the line that passes through (-2,1) and is a.)parallel to y = -3x + 4

Ex. 1 Write an equation of the line that passes through (-2,1) and is b.) perpendicular to y = -3x + 4

Ex. 2 Write a model using slope-intercept form The number of U.S. cell phone subscribers increased from 16 million in 1993 to 44 million to 1996. Find the average rate of change and use it to estimate the number of subscribers in 1997.

Assignment

Ex. 6 Write a model using standard form You have $6 to spend on drinks and a salad at the school cafeteria. The drinks cost $1.25 each and the salad costs $.20 per ounce. Write an equation that models this situation. 1.25x+.20y=6