1. Warm-Up Exercises In a computer generated image, a line is represented by the equation – 15. = 5y5y2x2x 1. Solve the equation for y and identify the slope of the line. 2. What should the slope of a second line in the drawing be if that line must be perpendicular to the first line? ANSWER y = 5 2 x 3;3; 5 2 – 2 5 –

2. Example 1 Write an Equation Given Slope and y -Intercept Write an equation of the line shown.

3. Checkpoint 1. 2. m = 2,2, 4b = –– 2 1 3. m = b= 5 –, 3,3, m = 1b = Write an equation of the line that has the given slope and y -intercept. Write an Equation Given Slope and y -Intercept

4. Example 2 Write an Equation Given Slope and a Point Write an equation of the line that passes through and has a slope of. () 2 4,4, 4 1 –

5. Checkpoint Write an equation of the line that passes through the given point and has the given slope. Write your equation in slope-intercept form. Write an Equation Given Slope and a Point 4. () 3 1,1, – = m2, 5. () 4,4, 5 – = m3 –, () 4 2,2, – = m5 6., () 3,3, – 3 – = m 3 2 7.,

6. Checkpoint Write an equation of the line that passes through the given point and has the given slope. Write your equation in slope-intercept form. Write an Equation Given Slope and a Point 8. () 0 8,8, 4 1 – = m, 9. () 10, 8 – = m 5 3,

7. Example 3 Write Equations of Parallel Lines Write an equation of the line that passes through and is parallel to the line. 5 = 2x2xy+ – () 4 1,1, –

8. Example 4 Write Equations of Perpendicular Lines Write an equation of the line that passes through and is perpendicular to the line. 5 = 2x2xy+ – () 4 1,1, –

9. Checkpoint Write an equation of the line described. 10.passes through ; parallel to () 6,6, – 5 – 2 = xy+ – 11.passes through ; perpendicular to () 6,6, – 5 – 2 = xy+ – 12.passes through ; parallel to () 3 2,2, – 1 = 4x4xy – Writing Equations of Parallel and Perpendicular Lines

10. Checkpoint Write an equation of the line described. 13.passes through ; perpendicular to () 3 2,2, – 1 = 4x4xy – Writing Equations of Parallel and Perpendicular Lines

11. Example 5 Write a Linear Model Condors In 1995 there were only 6 California condors living in the wild (all in California). In 2006 there were 138 California condors living in the wild (in California, Arizona, and Mexico). Write a linear model that represents the number of California condors living in the wild between 1995 and 2006.

12. Homework Writing Equations of Lines Homework: Page 97 #13-23 odd, 24-42 even,