1. Happy Monday! Warm-Up Write the equation and graph the line that has a slope of 2/3 and y-intercept of 1 Agenda Warm-Up Lesson Boss- Secretary Homework Time

2. Writing a Linear Equation Given a Point and a Slope Sections 4.2-4.3

3. Slope-Intercept form –Used to graph a line –Used to find equations of lines Point-Slope form –Used to find equations of lines Writing Equations of Lines Given Point and slope y = mx + b slope point ( x 1, y 1 ) y - y 1 =m(x - x 1 ) We will find the equation of a line given a point and a slope! What is point- slope form?

4. How do I find the equation of a line?

5. Example 1 Writing an Equation of a Line Write an equation in slope-intercept form of the line whose slope is m = -2 and passes through the point (6, -3).

6. Example 1 You Try!!! Find the equations of the lines:

7. Example 2 Writing an Equation of a Line Write an equation in slope intercept form of the line thru (2, 3) and (4, -5).

8. Example 2 We Try!!! Find the equations of the lines in slope-intercept form: Thru (-5, 4) and (-1, 6)

9. Example 2 You Try!!! Find the equations of the lines in slope-intercept form: Thru (0, 0) and (3, 1)

10. Example 3 Geometry Connection The figure shows trapezoid ABCD with bases AB and CD. Write an equation in point-slope form for the line containing the side BC. ___

11. Example 3 You Try!!! The figure shows trapezoid ABCD with bases AB and CD. Write an equation in point-slope form for the line containing the side AD. ___

12. Example 4 Real Life Linear Models Your parents refuse to take you Black Friday shopping, so you decide to take a taxi. The taxi service charges an initial fee of $3.50 plus $1.25 for every mile you need to travel. Write a linear equation that models y, the total cost, in terms of x, the miles traveled. What would the cost be if the store you want to go to is 6 miles away?

13. Example 4 You Try!!! A. y = 3.5 x + 57.65 B. y = 3.5 x + 68.15 C. y = 57.65 x + 68.15 D. y = –3.5 x – 10 The cost of a textbook that Mrs. Lambert uses in her class was $57.65 in 2005. She ordered more books in 2008 and the price increased to $68.15. Write a linear equation to estimate the cost of a textbook in any year since 2005. Let x represent years since 2005.

14. Boss Secretary Homework – Back side of the notes