Warm-Up Evaluate for x = -1, 0, and 2. 1.f(x) = 3x – 7 2. f(x) = -2x

Objectives: 1.Write linear equations given m and b. 2.Use linear equations in real life. Vocabulary: Slope-intercept Form Writing Linear Equations in Slope-Intercept Form 5.1

Slope-intercept Form: m = b = y = mx + b Writing Linear Equations in Slope-Intercept Form 5.1 slope of a line = y- intercept (0, b) rise run

Reviewing Chapter 4 Find the slope and y-intercept of these: y = 2x + 5 m = b =

Reviewing Chapter 4 Find the slope and y-intercept of these: y = -x – 3 m = b =

Reviewing Chapter 4 Find the slope and y-intercept of these: y = 4 m = b = What kind of line is this?

Reviewing Chapter 4 Find the slope and y-intercept of these: y = ½x + 4 m = b =

Reviewing Chapter 4 Find the slope and y-intercept of these: y = 3 – 7x m = b =

y = mx + b Writing Linear Equations in Slope-Intercept Form 5.1 How to find the equation of a line: 1.Find the slope (m) of the line. 2.Find the y-intercept (b) of the line. 3.Plug these values into y = mx + b m = 4 b = 3 y = 4x + 3

Example 1 Writing an Equation of a Line Write the equation of the line whose slope m = -2 and whose y-intercept b = 5. y = mx + b

Example 1 Writing an Equation of a Line Write the equation of the line whose slope and whose y-intercept. y = mx + b

Example 1 Writing an Equation of a Line Write the equation of the line whose slope and whose y-intercept. y = mx + b

Example 1 Writing an Equation of a Line Write the equation of the line whose slope m = 1 and whose y-intercept b = 7. y = mx + b

Example 2 Writing an Equation of a Line from a Graph Write the equation of the line shown in the graph y = mx + b Purple: Blue: Pink: Orange:

Example 3 A Linear Model for Population The number of trout in a lake was estimated to be 44.5 thousand in During the next 10 years, the trout population is expected to increase by about 3.2 thousand per year. Write a linear equation to model the trout population in any year between 1995 and Let t be the number of years since Predict the trout population in P = 3.2t ≈ 66.9 thousand trout

Guided Practice Please complete #3-11 on pg. 276 in your textbook. Raise your hand when you are done To be turned in for a classwork grade!

Tonight’s Homework pg. 276 #’s all, odd