2. SWBAT… Write lines in slope-intercept form Tues, 1/14 Agenda 1.WU/Review hw#2 (10 min) 2.5 Practice problems - slope-intercept form (20 min) 3.Quiz – slope and slope-intercept form (15 min) Warm-Up Given y = ½x + ¾, what is the slope and the y-intercept? HW3: Writing Equations in slope-intercept form

3. When an equation is in slope-intercept form: What is the slope? ____________ Now look at the equation below…… What is the y-intercept? ____________

4. Given y = ½x + ¾, what is the slope and the y-intercept? m = ½ b = ¾

5. Given y = ½x – ¾, what is the slope and the y-intercept? m = ½ b = -¾

6. Given y = -½x – ¾, what is the slope and the y-intercept? m = -½ b = -¾

7. y = mx+ b is an equation that defines a line A line has two characteristics –Points that fall on the line –Slope

8. Converting linear equations into Slope- Intercept Form 5 Examples

9. Slope intercept form is: y = mx + b Our main goal is to get the y alone on one side of the equation

10. Example 1 - convert into Slope-Intercept Form (divide both sides by 2 to get y alone) (now simplify all fractions) 21 What is the slope? _____What is the y-intercept? ______

11. Example 2 – Convert to Slope-Intercept Form -3y = -9x – 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 What is the slope? ____________ What is the y-intercept? ____________

12. *** Check Your Answer *** -3y = -9x – 12 (divide both sides by -3 to get y alone) (now simplify all fractions) y = 3x + 4 -3 -3y = -9x – 12 -3 -3 -3 Slope = 3 Intercept = 4 Wow, you’re good at this!!

13. Example 3: Convert to Slope-Intercept Form 21x – 7y =14 (subtract both sides by 21x) -7y = -21x + 14 (now divide both sides by -7) y = 3x – 2 (simplify all fractions) What is the slope? _________ What is the y-intercept? ________

14. 2y + 26 = -6x Step 1: Subtract both sides by 26 Step 2: Divide both sides by 2 to get y by itself Step 3: Simplify all fractions Example 4: Convert to Slope-Intercept Form What is the slope? ____________ What is the y-intercept? ____________

15. 2y + 26 = -6x (subtract both sides by 26) 2y = -6x – 26 (now divide both sides by 2 y = -3x – 13 (simplify all fractions) You are a math wizard! *** Check Your Answer ***

16. Example 5: In the standard (x, y) coordinate plane, what is the slope of the line given by the equation 5x – 4y = 3?

17. Families of Linear Graphs http://www.glencoe.com/sites/texas/ student/mathematics/assets/animati on/algebra1/ALG1CIM4-3.swf