SWBAT Write lines in slopeintercept form Tues 11910
SWBAT… Write lines in slope-intercept form Tues, 1/19/10 Agenda 1. WU (5 min) 2. Graphing Calculator Activity (30 min) 3. Discussion (15 min) 4. Exit slip (5 min) WU: Make the below corrections to the study guide: #30: B. (7/4, 0), (0, -7/5) #35: Change question: y = 3 x + 2 Complete Study Guide!
• #2 A) What conclusion can you make about the yintercept (b) and where it crosses the y-axis? • What ever the value of b is, that is where the line will cross the y-axis. • #2 B) How did the graph of y = x + 1 transform from the parent function y =x? • The line shifted up one unit.
What insight did you gain from this graphing calculator activity (4 th period) 1. That you can graph a line on a calculator and the calculator shows you the line 2. The m is always in front of the x 3. Step 1: First you plot the y-intercept (b) 4. Step 2: Then you plot m from where you left off 5. The y-intercept (b) is where b crosses the y-axis
What insight did you gain from this graphing calculator activity (2 nd period) 1. 2. 3. 4. 5. How to use a graphing calculator Y = mx + b, m is the number in front of x b is called the y-intercept Step 1: You use b to plot your first point Step 2: You then plot the slope from the y-intercept
What insight did you gain from this graphing calculator activity (6 th period) 1. Given y = mx + b, m is the number in front of x 2. Calculators can graph lines 3. b is the y-intercept 4. Step 1: First you plot the y-intercept onto the graph 5. Step 2: You then plot the slope from where you left off
SWBAT… Write lines in slope-intercept form Wed, 1/20/10 Agenda 1. Warm-up (5 min) 2. Notes on slope intercept – 5 examples (25 min) 3. Work on hw#3 (15 min) WARM-UP What is the slope and y-intercept of each equation: 1. 2. 3. 4. y y = = 4 x + 2 -x – 2 3 x -5 HW#3: Writing equations in slope-intercept form and COMPLETE STUDY GUIDE!!
Conclusion “I” from TI-83 Activity: • Graph #4 rises and graph #9 falls. This is because the slope of #4 is positive and the slope of #9 is negative. • The graph of #4 crosses on the negative side of the y-axis and the graph of #9 crosses on the positive side of the y-axis. This is because #4 has a y-intercept of -2 and #9 has a yintercept of 1.
Slope-intercept form: Now look at the equation below…… What is the slope? ______ What is the y-intercept? ______
Given y = 4 x + 2, what is the slope and the y-intercept? m=4 b=2
Given y = -x – 2, what is the slope and the y-intercept? m = -1 b = -2
Given y = 3 x, what is the slope and the y-intercept? m=3 b=0
Given y = -5, what is the slope and the y-intercept? m=0 b = -5
• y = mx+ b is an equation that defines a line • A line has two characteristics 1. Slope 2. Points that fall on the line
Converting linear equations into Slope. Intercept Form 5 Examples
Slope intercept form is: y = mx + b Our main goal is to get the y alone on one side of the equation
Example 1 - convert into slope-intercept form 2 1 (divide both sides by 2 to get y alone) (now simplify all fractions) Slope (m) = 2 y-intercept (b) = 1
*** Your turn – Example 2 – convert into slope-intercept form *** 5 y = 10 x + 15 5 2 3 y = 2 x + 3 Slope (m) = 2 y-intercept (b) = 3 (divide both sides by 5 to get y alone) (now simplify all fractions) BRAVO!!
*** Your turn – Example 3 – convert into slope-intercept form *** -3 y = -9 x – 12 Step 1: divide both sides by -3 to get y alone Step 2: Simplify all fractions Step 3: Write your equation in y = mx + b Slope (m) = y-intercept (b) =
*** Check Your Answer *** -3 y = -9 x – 12 -3 -3 -3 (divide both sides by -3 to get y alone) (now simplify all fractions) y = 3 x + 4 Slope (m) = 3 y-intercept (b) = 4
Example 4 - convert into slope-intercept form 21 x – 7 y = 14 -21 x (subtract both sides by 21 x) -7 y = -21 x + 14 (divide both sides by -7) -7 -7 -7(simplify all fractions) y = 3 x – 2 3 Slope (m) = 3 y-intercept (b) = -2 2
Example 5 - convert into slope-intercept form 2 y + 26 = -6 x Step 1: Subtract both sides by 26 Step 2: Divide both sides by 2 to get y by itself Step 3: Simplify all fractions Slope (m) = y-intercept (b) =
*** Check Your Answer *** 2 y + 26 = -6 x (subtract both sides by 26) (now divide both sides by 2 2 y = -6 x – 26 (simplify all fractions) y = -3 x – 13 Slope (m) = -3 y-intercept (b) = -13
HW#3 • Q 1 – 9: Similar to WU • Q 10 – 15: What we did today (solve for y) • Question 17 – 19: First find slope from the two points (using rise/run), then find the b (where the line crosses the y-axis. )
Fri, 2/22/10 http: //nlvm. usu. edu/en/nav/frames _asid_332_g_4_t_2. html? from=ca tegory_g_4_t_2. html
SWBAT… Write lines in slope-intercept form Thursday, 1/21/10 Agenda 1. Warm-up (2 min) 2. Review hw#3 (10 min) 3. Brain Pop video & quiz (8 min) 4. Review for test (30 min) WARM-UP 1. Take out hw#3 2. Take out study guide STUDY FOR FINAL!!!
• Red Cards = #1 • Black Cards: Insert a 1 in front of number. For example, a black 2 = 12.
- Slides: 26