I’m a little foggy – what is the slope of a line?

Slides:



Advertisements
Similar presentations
Objective - To find the slope of a line.
Advertisements

3.3 The Slope of a Line.
SLOPE AND PARALLEL AND PERPENDICULAR LINES.
Writing Parallel and Perpendicular Lines Part 1. Parallel Lines // (symbol) All parallel lines have the same slope. Parallel lines will NEVER CROSS. Since.
Parallel and Perpendicular Lines
Parallel & Perpendicular Lines
Perpendicular Lines. ┴ Perpendicular lines are lines that intersect in a right angle. ┴ The slopes of perpendicular lines are negative reciprocals of.
Section 3-6 Slope of Parallel and Perpendicular Lines SPI 22A: determine the equation of a line parallel or perpendicular to a given Objectives: Relate.
7.8 Parallel and Perpendicular Lines Standard 8.0: Understand the concepts of parallel and perpendicular lines and how their slopes are related.
Unit 1 Basics of Geometry Linear Functions.
Parallel & Perpendicular Lines. Parallel and Perpendicular Lines The two lines shown below are parallel (never intersect). Identify the slope of each.
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.
Parallel Lines Lines are parallel if they have the same slope.
Parallel & Perpendicular Lines
Section 7.3 Slope of a Line.
Slopes of Parallel and Perpendicular Lines Recall that two lines are parallel if they are in the same plane and do not intersect. Two lines are perpendicular.
Equations of lines.
Parallel and Perpendicular Lines
Slopes of Lines Chapter 3-3.
3.3 Slopes of Lines.
It’s What’s Going On!. Recall y = mx + b is the equation of a line m is the value of the slope of a line (rise over run) b is the y-intercept m = 1 __.
Linear Equations and Slope Created by Laura Ralston.
Everything You Will Ever Need To Know About Linear Equations*
3-7 Equations of Lines in the Coordinate Plane
Honors Geometry Section 3.8 Lines in the Coordinate Plane.
Honors Geometry Section 3.8 Lines in the Coordinate Plane.
3.4 – FIND AND USE SLOPES. Slope: measures the steepness of a line or the rate of change. Slope = m = Rise Run Up or down Left or right =
2.2 Slope and Rate of Change, p. 75 x y (x1, y1)(x1, y1) (x2, y2)(x2, y2) run (x2 − x1)(x2 − x1) rise (y2 − y1)(y2 − y1) The Slope of a Line m = y 2 −
4.4 Slope of a Line. Slope – a measure of how steep a line is. Slope is the ratio of the vertical change to the horizontal change of a non- vertical line.
8.2 Lines and Their Slope Part 2: Slope. Slope The measure of the “steepness” of a line is called the slope of the line. – Slope is internationally referred.
Parallel/ Perpendicular Lines Section 2.4. If a line is written in “y=mx+b” form, then the slope of the line is the “m” value. If lines have the same.
Chapter 3 Section 3. Objectives 1 Copyright © 2012, 2008, 2004 Pearson Education, Inc. The Slope of a Line Find the slope of a line, given two points.
WARM UP 1. Name the alternate interior angles 2. Name the alternate exterior angles 3. Name the corresponding angles.
Parallel Perpendicular lines
5-6 PARALLEL AND PERPENDICULAR LINES. Graph and on the same coordinate plane. Parallel Lines: lines in the same plane that never intersect Non-vertical.
Section 6.6 Parallel and Perpendicular Lines. Definitions Lines that lie in the same plane and never intersect are called parallel lines. All vertical.
Warm-Up. Slope Slope Objectives: Define slope as the ratio of vertical rise to horizontal run. Determine the slope of a line given a graph. Determine.
Slope Lesson 4.6.
Lines that are coplanar and do not intersect. Parallel Lines.
Chapter 5 Review. Slope Slope = m = = y 2 – y 1 x 2 – x 1 Example: (4, 3) & (2, -1)
1.5 Parallel and Perpendicular Lines on the Coordinate Plane
2-3C Parallel and Perpendicular Lines 2-3C Parallel and Perpendicular Lines Objectives: How do you know if slopes are parallel or perpendicular? What are.
3.4 Find and use Slope of Lines. Slope Slope is: Rate of change A ratio of rise and run The change in Y over the change in X The m is Y = mX +b.
Everything You Will Ever Need To Know About Linear Equations* *Whether You Wanted To Know It Or Not!
Parallel and Perpendicular Lines
5.6 Parallel and Perpendicular Equations
2.4 – Parallel and Perpendicular Lines
Parallel and Perpendicular Lines
Parallel and Perpendicular Lines
Parallel Lines: SLOPES ARE THE SAME!!
2.5 Linear Equations.
TEST 1-4 REVIEW 381 Algebra.
5-6 Parallel and Perpendicular Lines
Equations of Lines.
The ratio of vertical change to horizontal change
3-5: Vocabulary rise, run, slope point-slope form of a line
2-3C Parallel and Perpendicular Lines
Parallel and Perpendicular Lines
Section 3.6 Find and Use Slopes of Lines
WARM UP 1. Name the alternate interior angles
Monday, October 18 Slope of a Line
1.5: Parallel and Perpendicular Lines
TEST 1-4 REVIEW 381 Algebra.
Objective: Find the slope of a line given two point
Warm Up x – 5 = 0 Write the Standard Form equation of
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.
Slope Graphing Day 2.
2.2 Linear Equations.
Presentation transcript:

I’m a little foggy – what is the slope of a line?

Slope refers to the steepness of a line. Slope is described as rise run. The formula for slope is: y 2 - y 1 x 2 - x 1 This formula is used to find the slope of a line through the points (x 1, y 1 ) and (x 2, y 2 ).

Colored note card: Slope steepness of a line described as rise run formula for slope is: y 2 - y 1 x 2 - x 1 Horizontal line – slope = 0 Vertical line – slope is undefined Positive slope - Negative slope -

White note card Parallel and Perpendicular lines Parallel lines -coplanar -never intersect -symbol - // Perpendicular lines -coplanar -intersect to form 90° angles -symbol -  Skew lines -noncoplanar -never intersect

So, what about the slopes of parallel and perpendicular lines?

The slopes of parallel lines are equal! And the slopes of perpendicular lines are opposite reciprocals (their product is -1)! For perpendicular lines I just flip the slope and change to its opposite. That’s what I said!

Colored note card: Slopes of // and  lines slopes of parallel lines are the same slopes of perpendicular lines are opposite reciprocals (flipped and made opposites) Example: slope = ½ Slope of parallel line: Slope of perpendicular line: ½ - 2 / 1 or -2

Find the slope of a line parallel and a line perpendicular to the given line. the line through (-5, 2) with a slope of ¾ y = -3x + 4 the line through (-2, 6) and (4, -1)

The fog is clearing! Just to review: parallel lines never intersect and perpendicular lines intersect to form right angles. The slopes of parallel lines are equal. The slopes of perpendicular lines have a product of -1 - or they are opposite reciprocals. I think I’ve got it!

1.All five of the lines below are to be graphed on the same coordinate graph. Without graphing, describe how the graphs of the lines are related (parallel, perpendicular, intersecting). Justify your answers (you could set up your answer as a two column table). Line a - y = -5/2 x + 6 Line b - through (1, -4) with slope 2/5 Line c - through (7, 10) and (13, -5) Line d - y = 2x - 15 Line e - through (5, 8) and (15, 12)

2.Graph each of the lines from #1 on the same coordinate graph. Label each line. Were the relationships you described in #1 correct? Line a - y = -5/2 x + 6 Line b - through (1, -4) with slope 2/5 Line c - through (7, 10) and (13, -5) Line d - y = 2x - 15 Line e - through (5, 8) and (15, 12) 3.Write the equation of a line that is perpendicular to line e. Write the equation of a line that is parallel to line e.